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El objetivo de este estudio fue analizar la relación existente entre variables relativas a la motivación de logro como son la percepción de competencia autopercibida, la percepción de competencia comparada, el compromiso y entrega en el aprendizaje en Educación Física y la ansiedad ante el fracaso y situaciones de estrés con el índice de masa corporal. Dicho análisis se realizó por sexos puesto que se encontraron diferencias y razones en la literatura. En este estudio participaron un total de 846 adolescentes escolarizados en la comunidad autónoma de Aragón cuya edad media fue de 13,65 años (DE = 1,27), de los cuales 446 (52,71%) fueron hombres y 400 (47,29%) fueron mujeres. Todos ellos contestaron al cuestionario AMPET4 y se les tomó el peso y la talla para después calcular su índice de masa corporal. El estudio de la normalidad derivó en el uso de pruebas no paramétricas, utilizando para el análisis las pruebas de U Mann-Whitney y Rho de Spearman. Tomando el grupo completo, se encontraron correlaciones inversas pero con pequeño efecto entre las variables de. percepción de competencia autopercibida, percepción comparada y compromiso en el aprendizaje en las clases de Educación Física y el IMC. Por sexos, tanto en el caso de los chicos como de las chicas solo hubo correlación inversa en la percepción autopercibida y la percepción de competencia comparada con el IMC. Por otro lado, los chicos se perciben más competentes tanto de forma autopercibida como comparada que las chicas, mientras que estas sienten más ansiedad y agobio frente al fracaso en las clases de EF que los chicos. Palabras clave. Motivación de logro, percepción de competencia, IMC, Educación Física, Educación Secundaria, sexos Abstract. The aim of this study was to analyze the relationship between variables related to achievement motivation such as self-perceived competence perception, comparative competence perception, commitment and dedication to learning in Physical Education, and anxiety about failure and stressful situations with body mass index. This analysis was carried out by sex since differences and reasons were found in the literature. A total of 846 adolescents in school in the autonomous community of Aragón participated in this study, with a mean age of 13.65 years (SD = 1.27), of whom 446 (52.71%) were male and 400 (47.29%) were female. All of them answered the AMPET4 questionnaire and their weight and height were taken and then their body mass index was calculated. The study of normality led to the use of nonparametric tests, using the Mann-Whitney U and Spearman's Rho tests for the analysis. Taking the whole group, inverse correlations were found, but with a small effect between the variables of self-perceived competence, comparative perception and commitment to learning in Physical Education classes and BMI. By sex, in the case of both boys and girls there was only inverse correlation in self-perceived perception and perception of competence compared to BMI. On the other hand, boys perceived themselves more competent both self-perceived and comparatively than girls, while girls felt more anxiety and overwhelm in the face of failure in PE classes than boys. Keywords: Achievement motivation, perception of competence, BMI, Physical Education, Secondary Education, gender.

Introducción. El embarazo es un proceso fisiológico que produce alteraciones en los patrones del sueño. A nivel fisiológico la falta de sueño se relaciona con problemas de salud tales como hipertensión, enfermedad coronaria, diabetes y depresión. En el embarazo, las alteraciones del sueño son más frecuentes siendo su prevalencia mayor durante el tercer trimestre. La deprivación del mismo durante el embarazo empeora significantemente las condiciones preexistentes de la mujer disminuyendo la actividad física diaria, la productividad y aumentando los síntomas relacionados con el estrés. Las alteraciones del sueño en el embarazo se pueden relacionar con comorbilidad en el recién nacido y resultados adversos materno-fetales. Objetivos. Determinar qué alteraciones del sueño ocurren durante el embarazo, cuáles son sus causas y qué posibles consecuencias podría tener el déficit de sueño durante la gestación a nivel materno-fetal y neonatal. Metodología. Se llevó a cabo una revisión sistemática siguiendo los principios de la declaración PRISMA. Se recogieron tanto estudios observacionales como de intervención así como revisiones sistemáticas y meta- análisis y se llevó a cabo un análisis crítico de los resultados. Resultados y discusión. Se incluyeron finalmente un total de 19 artículos que trataban sobre los efectos de las alteraciones del sueño en los resultados materno-fetales y neonatales y sus causas. Las principales causas de las alteraciones del sueño son los cambios hormonales y fisiológicos propios del embarazo como es el aumento de peso que se hacen más prevalentes conforme progresa la gestación. Las consecuencias maternas engloban principalmente trastornos respiratorios, alteraciones cardiovasculares e inflamatorias y resultados adversos del embarazo como es la cesárea. Los resultados adversos en el recién nacido más estudiados son partos prematuros y recién nacidos con bajo peso para la edad gestacional. Conclusión. Con este trabajo se observa que existe una relación entre los trastornos del sueño durante el embarazo y los problemas materno –fetales. Sin embargo, los estudios llevados a cabo hasta la fecha son heterogéneos, emplean herramientas subjetivas y sus conclusiones resultan en ocasiones contradictorias.

We thank the families who collaborated with this study: parents, grandparents, and children. We also thank the institutions and professionals who helped make it possible, including the Faculty of Health Sciences, University of Granada; the University Hospital Complex of Granada; the health centers of Granada; and the Los Cármenes School of Early Childhood and Primary Education (Granada)., Background: in recent years the prevalence of obesity in infants, children, and adolescents has increased alarmingly, which may affect their health, educational level, and quality of life. Objectives: the aim of this study was to determine whether a program with physical activity and nutritional recommendations may improve health-related quality of life (HRQL) in overweight and obese children. Material and methods: the design of this study was that of a randomized clinical trial (RCT). The sample consisted of 54 children with a median age of 10.65 years, all of them overweight or obese. They were divided into a study (SG) and a control (CG) group, with 27 children each. The study group received physical activity and nutritional advice, while the control group only received theoretical-practical sessions on nutrition during 9 months. Families participated in the workshops on nutritional recommendations in both groups. Results: there was a significant difference in fat percentage before and after the intervention in the study group compared to the children who did not engage in sports activity. In the SF-10 quality-of-life perception questionnaire, statistically significant differences in both the physical and mental components may be seen at the end of the study between both groups (p < 0.001). Conclusions: an educational intervention with physical activity based on play and nutritional advice improved quality of life in overweight and obese children. Family involvement is vital for children to improve their life habits, and achieve favorable results in the reduction of overweight and obesity., Introducción: en los últimos años, la prevalencia de la obesidad en los bebés, niños y adolescentes ha aumentado de forma alarmante, lo que podría afectar a su salud, nivel educativo y calidad de vida. Objetivos: el objetivo de este estudio fue determinar si un programa con actividad física y recomendaciones nutricionales puede mejorar la calidad de vida relacionada con la salud (CVRS) en niños con sobrepeso y obesidad. Material y métodos: el diseño de este estudio fue el de un ensayo clínico aleatorizado (ECA). La muestra consistió en 54 niños de 10,65 años de edad mediana con sobrepeso u obesidad. Se dividieron en grupos de estudio (SG) y de control (CG), ambos con 27 niños. El grupo de estudio recibió actividad física y asesoramiento nutricional mientras que el grupo de control solo recibió las sesiones de nutrición teórico-prácticas durante 9 meses. Las familias participaron en los talleres sobre recomendaciones nutricionales en ambos grupos. Resultados: hubo una diferencia significativa en el porcentaje de grasa antes y después de la intervención en el grupo de estudio en comparación con los niños que no participaron en la actividad deportiva. En el cuestionario de calidad de vida SF-10 se puede observar que existen diferencias estadísticamente significativas en los componentes físicos y mentales al final del estudio entre ambos grupos (p < 0,001). Conclusiones: una intervención educativa con actividad física basada en el juego y asesoramiento nutricional mejoró la calidad de vida de estos niños obesos y con sobrepeso. La participación familiar es vital para que los niños mejoren sus hábitos de vida y logren resultados favorables en la reducción del sobrepeso y la obesidad.

Background: Sleep disorders are associated with overweight and obese children, and could decrease life quality with limitations to normal daily activities. The purpose of the study is to describe the prevalence of sleep disorders in a cohort of overweight/obese children using respiratory polygraphy. Methods: A descriptive cross-sectional study was conducted in Granada (Spain) on a sample of 98 children with overweight or obesity. The presence of sleep disorders was determined by respiratory polygraphy. Results: Regarding apnoea&ndash, hypopnea-index (AHI) results, 44% of affected children had severe sleep apnoea&ndash, hypopnea syndrome (SAHS), and the remaining 56% had a mild form of the disorder. With respect to oxygen-desaturation index, 56% of the same group had severe SAHS, 32% had mild SAHS, and the remaining 12% did not suffer from SAHS. Among participants, average scores of 13.8 obstructive apnoea, 7.7 central apnoea, and 13.6 hypopnoea were recorded. Conclusions: Respiratory polygraphy can provide conclusive results in the diagnosis of SAHS in overweight/obese children. Interventional programmes designed and implemented to reduce overweight and obesity can improve quality of sleep and life in children.

Antecedentes: El presente estudio, parte de una revisión bibliográfica anterior sobre las técnicas de tratamiento en piscina para los pacientes afectados de Parálisis Cerebral Infantil (PC). Al no encontrar diferencias significativas entre los distintos métodos y técnicas utilizados, diseñamos un programa de ejercicios según el modelo del desarrollo psicomotor del niño sano, implementándolo y valorando su eficacia en el tratamiento de personas con esta patología haciendo un uso de la hidroterapia orientado hacia los aspectos estructurales, funcionales y sociales en el proceso global de la rehabilitación. Objetivos: El objetivo de este estudio es valorar la evolución que se produce en la función motora gruesa en niños afectados de PC, después de seis meses de tratamiento. Método: Se trata de un estudio longitudinal prospectivo sobre 12 pacientes con edades comprendidas entre 18 y 33 meses al comienzo, 9 niños y 3 niñas. El protocolo de tratamiento consiste en una sesión semanal de 30 minutos de los cuales, 20 se realizan íntegramente en piscina. Se evaluó mediante la Escala validada Gross Motor Function Measure (GMFM) antes de realizar hidroterapia y a los seis meses de iniciar la intervención. No se ha utilizado grupo control debido a que la diversa sintomatología propia de esta patología lo desaconseja. Cada paciente es su propio control entre el pre y post-test. Resultados: Se observa una mejoría, estadísticamente significativa, en la escala global GMFM y en aspectos específicos de las subescalas: a) Tumbado y rodando, b) Sentado, c) Gateando y de rodillas, d) de pie, e) Andando, corriendo, saltando. Conclusiones: La hidroterapia promueve el desarrollo de habilidades motoras gruesas en niños afectados por PC. También contribuye a un desarrollo positivo en la curva GMFM normal y una mejora posterior a la intervención en los percentiles correspondientes. Background: This study is based on a previous literature review of hydrotherapy techniques for patients with cerebral palsy (CP). This review found no significant differences between the different methods and techniques considered, and therefore a hydrotherapy protocol was developed, according to the model of psychomotor development achieved by a child in good health, in order to assess its efficacy in the treatment of children with CP. The hydrotherapy was oriented towards structural, functional and social aspects of the patient’s condition, within the overall rehabilitation process. Goals: To evaluate the changes observed in the gross motor function of children affected by CP, at baseline and after six months of hydrotherapy. Method: A prospective longitudinal study was conducted of 12 patients aged 18-33 months at the beginning (9 boys and 3 girls). The intervention protocol consisted of a 30-minute session performed once weekly, with 20 minutes in the pool. Gross motor function was assessed using the validated gross motor function measure (GMFM) scale prior to hydrotherapy and at six months after initiating the treatment. There was no control group, since the diverse symptoms typical of this pathology made it impractical. Instead, each patient constituted their own control, pre and post-test. Results: A statistically significant (p≤0.001) improvement was measured, on the GMFM global scale and on the following subscales: a) lying and rolling; b) sitting; c) crawling and kneeling; d) standing; e) walking, running and jumping. Conclusions: Hydrotherapy promotes the development of gross motor skills in children affected by CP. It also contributes to a positive development in the normal GMFM curve and a post-intervention improvement in the corresponding percentiles. Introduçao: O presente estúdio, parte de uma revisão bibliográfica anterior sobre as técnicas de tratamento em piscina para pacientes afetados pelo paralisia cerebral infantil (PC). Se você não encontrar diferenças diferenciadas entre os métodos e técnicas utilizadas, desenhe um programa de exercícios segundo o modelo de desenvolvimento psicomotor do filho sano, implemente e avalie a eficácia no tratamento de pessoas com esta patologia que usa o uso do hidroterapeuta orientado aspectos estruturais, funcionais e sociais no processo global de reabilitação. Objetivos: O objetivo deste estúdio é avaliar a evolução que produz a função motora grega nos menores afetados pelo PC, menos seis meses após o tratamento. Método: trata-se de um estúdio longitudinal prospectivo de 12 pacientes com idades compreendidas entre 18 e 33 meses de idade, 9 anos e 3 anos. O protocolo de tratamento consiste em uma sessão semanal de 30 minutos dos códigos, 20 a ser realizada diretamente na piscina. Se você avaliar usando a Escala de Função Motora Bruta (GMFM) validada antes de realizar a hidroterapia e os seis meses após o início da intervenção. Não há um grupo de controle usado que debita a sintomatologia apropriada dessa patologia para a desaconselhidão. Cada paciente é o controle adequado entre o pré e o pós-teste. Resultados: Se você observar uma diferença estatisticamente significativa, na escala global GMFM e nos aspectos das subescalas: a) Tumbado e rodando, b) Sentado, c) Gatilho e rodillas, d) torta, e) Andando, corrigindo , saltando. Conclusões: A hidroterapia promove o desenvolvimento de habilidades motoras em animais afetados por PC. Também contribuímos com um projeto positivo na curva GMFM normal e em uma parte posterior da intervenção nos percentis correspondentes.

El trabajo que se presenta recoge la experiencia de un proyecto de coordinación interdisciplinar entre tres asignaturas de la mención de educación física del grado en magisterio en educación primaria (actividades físicas individuales, actividades físicas de oposición y colaboración, y actividades físicas artístico-expresivas) en torno al contenido del acrosport. Se establecieron dos objetivos: identificar las diferencias significativas en cuanto a las calificaciones obtenidas en el proyecto según la matrícula en las tres asignaturas integradas; y analizar la valoración del alumnado sobre la aportación de las asignaturas implicadas en el proyecto, el trabajo autónomo y la adquisición de las competencias transversales. Participaron 66 alumnos/as de una media de edad de 22,90 años, 34 alumnos y 32 alumnas, todos ellos pertenecientes a la mención de educación física del grado de maestro de primaria de la facultad de educación de Zaragoza (universidad de Zaragoza). Para llevar a cabo el primer objetivo se diseñó una rúbrica para calificar por parte del profesorado los proyectos de acrosport. Para desarrollar el segundo objetivo se diseñó un cuestionario de valoración del alumnado sobre el proyecto. Los resultados extraídos a partir de las evaluaciones del profesorado muestran diferencias significativas positivas de las calificaciones del alumnado matriculado en las tres asignaturas implicadas. Los resultados procedentes de las valoraciones del alumnado sobre la aportación de las asignaturas implicadas revelan puntuaciones menores en la asignatura actividades físicas artístico-expresivas. Las valoraciones del alumnado en torno al trabajo autónomo y la adquisición de las competencias transversales obtuvieron altas puntuaciones. Abstract. This study is based on the experience of a coordinated interdisciplinary project around the content of acrosport involving three subjects (individual physical activities; competitive and collaborative physical activities; artistic-expressive physical activities) that form a part of the Physical Education module of the Primary Education Teaching Degree at the University of Zaragoza, Spain. There were two objectives: i) To identify significant differences in the grades obtained by the students in the three integrated subjects that comprised the project. ii) To analyze the evaluation and opinions of the students regarding the value of the subjects, the individual work and the acquisition of transversal competences. The study group was made up of 66 students with an average age of 22.9 years. There were 34 men and 32 women. All the participants were studying the Physical Education module of the Primary Education Degree at the Zaragoza University Faculty of Education. The teachers involved with the module designed a rubric to assess the acrobatic gymnastics project. To understand students’ opinions regarding the project, a questionnaire was designed. The results of the grades given to the students by the teachers showed significant differences in the three subjects. The results of the evaluations given by the students were lower for the subject of artistic-expressive physical activities. The students gave very high scores for the evaluation of individual work and the acquisition of transversal competences.

Introduction: The aquatic environment has been used and is used to perform physiotherapy treatments in different pathologies including cerebral palsy. No method has been proven more effective than the others. Aim: The objective of this article is to carry out a systematic review of the scientific literature on how physical exercise in water affects the gross motor skills and neurodevelopment of children with cerebral palsy. Methods: A systematic search was carried out using the PRISMA model. The search for articles in this review was done in the databases through Scopus and PubMed, as well as in the Web of Science (WOS) platform and in official websites of international organizations, such as the World Health Organization (WHO). The review was carried out between the months of June and December of the year 2016. Results: Of the 8 studies that met the inclusion criteria, only two used randomized control trial design and the results were mixed. Most of the studies used quasi-experimental designs and reported improvements in gross motor skills, for group analyzes, after the aquatic programs were maintained from two to three sessions a week and lasted from 6 to 16 weeks. Participants were evaluated and classified according to the different development scales, and were less than 5 years old. Conclusions: Although the different studies have not demonstrated a greater efficacy of aquatic physiotherapy compared to other treatment concepts, neither has been less, so that the exercise in water increases the therapeutic possibilities to which the chronic nature of the Pathology must access the patient throughout his life. Aquatic exercise is feasible and adverse effects are minimal; but the dosage parameters are not clear. However, in order to promote the prescription by physicians of this type of therapy, it is necessary to carry out research studies that demonstrate in a quantitative way the efficacy of the method, with longer and longer samples.

Introduction: According to some authors, aquatic environment offers advantages for motor development, which can be used from the first months of life. The current research reviewed support physical exercise in water is favorable for the neurodevelopment of the baby. At present there are few studies with a scientific methodology that have developed a physical activity programme in babies in the first 3 years of life. Therefore, in this study, an aquatic physical activity programme will be performed to check how it affects the sensorymotor development and affectivity of healthy babies in their first years of life. Objectives: To determine the relationship between physical activity in water and the development of psychomotricity in healthy babies in their first three years of life. Material and methods: A case-control study was accomplished with 74 infants in the intervention group and 71 in the control group. The programme is carried out twice a week and lasts for 20 min in the water. It starts at 3 months and lasts three years of age. The activity is performed in the therapeutic swimming pool of the Complejo Hospitalario Universitario of Granada. In the first trimester, between the 3 and 6 months of life, we join in the adaptation to the aquatic environment, the interrelation between the babies and their parents, the first motor skills, supine and prone positions, flips and the beginning of sedestation and dives. In the second trimester, between the 6 and 9 months of life, we intervene on displacements and crawling. And in the third quarter, between the 9 months and the first year of life, we participate on the equilibria-imbalances, displacements, standing, march and dips. The second and third year will be carried out group aquatic activities to encourage, through play, motor skills in the water. Expected results: Aquatic physical activity improves neurodevelopment, sleep and affectivity in healthy babies.

The capability of UVM-7 silicas to work as supports for drug storage and delivery is investigated using ibuprofen as a model. UVM-7 silicas are surfactant-assisted synthesised mesoporous materials displaying a characteristic bimodal pore architecture related to their nanoparticulate texture. Strict control of the drug-charge protocol allows the achievement of high ibuprofen loads, not only because of the availability of intra-nanoparticle mesopores and large textural voids, but also owing to the decrease in pore-blocking effects (with regard to related unimodal mesoporous materials such as MCM-41) achieved through the shortening of the mesopore length. The UVM-7/ibuprofen nanocomposites are characterised using XRD, TEM and N2 adsorption/desorption isotherms, and the drug-delivery processes are monitored by spectrometric techniques. The bimodal porosity results in two-stage drug-delivery processes, which are analysed through kinetic models.

Quantum chemical calculations using density functional theory have been carried out to investigate two chemical pathways for the last step of the hydrolysis of tetraethylorthosilicate (TEOS) in basic catalyzed environment. The two models that are introduced in this study depend on the number of water molecules involved at the base catalyzed hydrolysis. Solution equilibrium geometries of the molecules involved in the transition states, reactants and product complexes of the two chemical pathways were fully optimized at B3LYP level of theory with the standard 6-31+G(d) basis set, modeling solvent effects using a polarizable continuum solvation model (PCM). Both models predict relative low activation energies. However, the model with two water molecules seems to be more adequate to describe the basic hydrolysis. A natural bond orbital (NBO) analysis seems to show that the proton transfer from water to ethoxy group would occur through a large hyperconjugative interaction, LP(O) → σ*(O-H), which is related to the nonbonding oxygen lone pair orbital from ethoxy group with the vicinal σ*(O-H) anti bonding orbital O-H of a water molecule.

at present, diabetes has become a global health problem. The consequences that entails, both short and long term, do more studies and knowledge necessary for detection, control and treatment. Moreover, its prevalence is increasing in both the general population and pregnant women. Numerous effects and complications have been reported in infants of diabetic mothers, such as fetal macrosomia, hypoglycemia and increased risk of developing obesity. This condition could have negative effects on the neurological development of the child and could affect his intellectual capacity and increase cognitive impairment.to analyze the studies which have investigated in the relationship between diabetes mellitus during pregnancy and its impact on child neurodevelopment short and long-term.we performed a systematic search and 20 specific articles on the subject selected would be selected following the PRISMA guidelines.in the studies consulted include a large methodological variety in both instruments and cognitive assessment scales, as in the age at which the sample is studied. However, most researchers conclude that maternal diabetes can have consequences for the child, both short and long-term. A higher rate of obesity, impaired glucose tolerance, cardiovascular and metabolic disorders and neurodevelopmental impairment is also described, which increase the neurobehavioral disorders and intellectual disability.most of the studies are agree in describing neurodevelopmental disorders in children of diabetic mothers, both in cognition and in the specific areas related to expressive language, social relations, graphical skills and psychomotor development. Other research has linked maternal diabetes with an increased incidence of autism spectrum disorders such as hyperactivity, attention deficits and schizophrenia.Introducción: en la actualidad, la diabetes se ha convertido en un problema de salud mundial. Las consecuencias que conlleva, tanto a corto como a largo plazo, hacen necesarios más estudios y conocimientos para su detección, control y tratamiento. Además, su prevalencia va en aumento, tanto en la población general como en las mujeres embarazadas. Se han descrito numerosos efectos en los bebés de madres diabéticas, tales como macrosomía fetal, hipoglucemia y un riesgo mayor de desarrollar obesidad en el futuro. Esta patología puede tener efectos negativos en el desarrollo neurológico del niño, pudiendo afectar a su capacidad intelectual, aumentando así las alteraciones cognitivas. Objetivo: analizar los estudios que han investigado la relación existente entre la diabetes mellitus durante el embarazo y su influencia en el neurodesarrollo del niño a corto y largo plazo. Métodos: se lleva a cabo una búsqueda sistemática y se seleccionan 20 artículos específicos sobre el tema, siguiendo las directrices PRISMA. Resultados: en los estudios consultados cabe destacar una gran variedad metodológica, tanto en los instrumentos y escalas de valoración cognitiva como en la edad en la que se estudia la muestra. Sin embargo, la mayor parte de los investigadores concluyen que la diabetes materna puede tener consecuencias en el niño, tanto a corto como a largo plazo. También se describe una mayor tasa de obesidad, intolerancia a la glucosa, trastornos cardiovasculares y metabólicos y afectación del neurodesarrollo, pues aumentan los trastornos neuroconductuales y la discapacidad intelectual. Conclusiones: la mayoría de los estudios consultados coinciden en describir alteraciones del desarrollo neurológico en los hijos de madres diabéticas, tanto en la capacidad cognitiva como en las áreas concretas relacionadas con el lenguaje expresivo, las relaciones sociales, las habilidades gráficas y el desarrollo psicomotor. Asimismo, otros trabajos de investigación han relacionado la diabetes materna con un aumento de la incidencia de trastornos del espectro autista, como hiperactividad, déficit de atención y esquizofrenia.

Mesostructured layered silicas have been prepared through a surfactant-assisted procedure using neutral alkylamines as templates and starting from atrane complexes as hydrolytic inorganic precursors. By adjusting the synthetic parameters, this kinetically controlled reproducible one-pot method allows for obtaining both pure and functionalized (inorganic or organically) lamellar silica frameworks. These are easily deconstructed and built up again, which provides a simple way for expanding the interlamellar space. The materials present high dispersibility, which results in stable colloidal suspensions.

The synthesis of two new ligands constituted of a tris(2-aminoethyl)amine moiety linked to the 2,6 positions of a pyridine spacer through methylene groups in which the hanging arm is further functionalized with a 2-pycolyl (L1) or 3-pycolyl (L2) group is presented. The protonation of L1 and L2 and formation of Cu(2+) complexes have been studied using potentiometric, NMR, X-ray, and kinetic experiments. The results provide new information about the relevance of molecular movements in the chemistry of this kind of so-called scorpiand ligand. The comparison between these two ligands that only differ in the position of the substituent at the arm reveals important differences in both thermodynamic and kinetic properties. The Cu(2+) complex with L1 is several orders of magnitude more stable than that with L2, surely because in the latter case the pyridine nitrogen at the pendant arm is unable to coordinate to the metal ion with the ligand acting as hexadentate, a possibility that occurs in the case of [CuL1](2+), as demonstrated by its crystal structure. Significant differences are also found between both ligands in the kinetic studies of complex formation and decomposition. For L1, those processes occur in a single kinetic step, whereas for L2 they occur with the formation of a detectable reaction intermediate whose structure corresponds to that resulting from the movement typical of scorpiands. Another interesting conclusion derived from kinetic studies on complex formation is that the reactive form of the ligand is H(3)L(3+) for L1 and H(2)L(2+) for L2. DFT calculations are also reported, and they allow a rationalization of the kinetic results relative to the reactive forms of the ligands in the process of complex formation. In addition, they provide a full picture of the mechanistic pathway leading to the formation of the first Cu-N bond, including outer-sphere complexation, water dissociation, and reorganization of the outer-sphere complex.

ZnO nanodomains embedded in bimodal mesoporous silica (UVM-7) materials with high Zn content (4≤Si/Zn≤30) have been synthesized by an one-pot surfactant-assisted procedure from a hydro alcoholic medium using a cationic surfactant (CTMABr=cetyltrimethylammonium bromide) as structural directing agent, and starting from molecular atrane complexes of Zn and Si as hydrolytic inorganic precursors. This chemical procedure allows optimizing the dispersion of the ZnO particles in the silica walls. The bimodal mesoporous nature of the final high surface area nano-sized materials is confirmed by XRD, TEM, and N2 adsorption–desorption isotherms. The small intra-particle mesopore system is due to the supramolecular templating effect of the surfactant, while the large pores have their origin in the packing voids generated by aggregation of the primary nanometric mesoporous particles. A limited pore blocking and a high accessibility to the ZnO active nanoparticles have been achieved. The effects induced by the progressive incorporation of ZnO nanoparticles into the mesostructure have been examined, including a careful optical spectroscopic study (PL and UV–visible).

High surface area pure mesoporous aluminum-phosphorus oxide-based derivatives have been synthesized through an S+I− surfactant-assisted cooperative mechanism by means of a one-pot preparative procedure from aqueous solution and starting from aluminum atrane complexes and phosphoric and/or phosphorous acids. A soft chemical extraction procedure allows opening the pore system of the parent as-prepared materials by exchanging the surfactant without mesostructure collapse. The nature of the pore wall can be modulated from mesoporous aluminum phosphate (ALPO) up to total incorporation of phosphite entities (mesoporous aluminum phosphite), which results in a gradual evolution of the acidic properties of the final materials. While phosphate groups in ALPO act as network building blocks (bridging Al atoms), the phosphite entities become basically attached to the pore surface, what gives practically empty channels. The mesoporous nature of the final materials is confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and N2 adsorption–desorption isotherms. The materials present regular unimodal pore systems whose order decreases as the phosphite content increases. NMR spectroscopic results confirm the incorporation of oxo-phosphorus entities to the framework of these materials and also provide us useful information concerning the mechanism through which they are formed.

A diversity of silica-based and non-silica nanoparticulated mesoporous xerogels have been synthesized from aqueous solution using a surfactant-free strategy, and starting from molecular atrane complexes as precursors. This approach constitutes an extension of the “atrane route” previously described for the surfactant-assisted synthesis of mesoporous materials, and allows us to unify the multiplicity of protocols described for the preparation of conventional xerogels. In fact, we have used exactly the same preparative conditions for obtaining all the compositions reported here. The xerogels synthesized in this way include pure silica (UVM-11), aluminosilicates and titanosilicates (M-UVM-11, M = Al, Ti), hybrid organic–inorganic silica-based derivatives, and also non-silica materials such as pure titania and alumina. Moreover, post-hydrothermal treatments allow modulating the mesopore average size in the ca. 3–30 nm range. The key factor making available such a diversity of materials is the inertness of the atrane complexes, which allows orchestrating the hydrolytic reactivity of different oxide-forming elements. In turn, this avoids subsequent phase segregation and results in chemically homogeneous materials.

Composites of silica nanospheres coated with crosslinked epoxy–amine were synthesised and examined by 29Si-magic-angle-spinning nuclear magnetic resonance spectroscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy and scanning electron microscopy. The most representative fact is that epoxy-modified nanospheres lost less weight at high temperatures. At temperatures greater than 300°C the loss of weight for epoxy-modified nanospheres was rather lower than for unmodified nanospheres. This helped them to retain their structures, as the loss of weight can have adverse effects on network defects, due to the loss of crosslinks by unit of volume.

Quantum chemical calculations using density functional theory have been carried out to investigate molecular precursors based on alumatranes which are one of the components with silatranes for the preparation of mesoporous aluminosilicate materials. In the same way, some oligomeric alumatranes of this study take part in chemical syntheses related to materials such as zeolites and alumina composite. Gas phase and solution equilibrium geometries of the alumatrane precursors were fully optimized at B3LYP level, modeling solvent effects using a self-consistent reaction field (SCRF). From these optimized geometries, calculations of the 1 H, 13 C and 27 Al NMR chemical shifts at GIAO/B3LYP/6-31G(d,p) levels of theory have also been performed. This study has shown that the assumed conformations of the alumatrane precursors that have been derived from a previous work on a FAB-MASS analysis (Fast Atomic Bombardment Mass Spectroscopy) are confirmed by DFT calculations. All the conformations of alumatranes show that there would have transannular Al–N bond. Oligomeric alumatranes are composed of one or more two-membered Al2O2 rings where tricoordinated oxygen would be present. A good agreement between the experimental NMR data and the theoretical study on the chemical shifts of nucleus as 13 C, 1 H and 27 Al from full geometry optimizations of the alumatrane precursors seems to corroborate the presence of the alumatrane precursors in the ‘‘atrane route’’.

Quantum chemical calculations using density functional theory have been carried out to investigate two assumed molecular precursors and identified as silatranes (N[OCH2CH2]3Si–OCH2CH2N–(CH2CH2OH)2 and N[OCH2CH2]3Si–OCH2CH2N–(CH2CH2OH)2Na+) which are present in the synthesis of mesoporous silica based material namely “the atrane route”. One of the ways in this synthesis leads to the well-known MCM-41. Additionally, in this work has been also investigated two others molecules such as triethanolamine (TEAH3) and sodatrane which are present in the medium. Gas phase and solution equilibrium geometries of the previous molecules were fully optimized at B3LYP level, modeling solvent effects using a self-consistent reaction field (SCRF) Onsager model, a discrete electrostatic representation of triethanolamine molecules in the first solvation shell. Calculations of the 1H and 13C NMR chemical shifts at GIAO/B3LYP/6–31G(d,p) levels of theory are also presented. The importance of basis set is previously discussed in the GIAO calculations. Finally, a natural bond orbital (NBO) analysis has been performed to provide insight into the role of electronic delocalization in the chemical shielding. This work has shown that the assumed geometries of the molecular precursors that have been deduced from a previous work on a FAB-MASS analysis (Fast Atomic Bombardment Mass Spectroscopy) are confirmed by DFT calculations. The theoretical study on the chemical shifts of nucleus as 13C and 1H from full geometry optimizations of the molecular precursors and sodatrane describes hydrogens bonded to each CH2O and CH2N groups as not equivalent; in the same way, it appears that some carbons are not magnetically equivalent. GIAO calculations from a full geometric optimization of TEAH3 overestimate the experimental chemical shifts; however, a threefold-symmetry (C3) of optimized geometry yields an improvement of the theoretical chemical shifts. The discrepancies in the GIAO calculations might be related to the hyperconjugative interactions such as LPO1 → σ*(C–X), LPO2 → σ*(C–X) and LPN → σ*(C–X) with X = C, H and also σ → σ*(C–X) with X = O; N, H. These interactions are characterized by delocalization energies which are generally important and peculiarly for LP → σ*(C–X). A reasonable level of agreement between GIAO calculations and experimental NMR studies is obtained which confirms the presence of the molecular precursors in the “atrane route” and taking into account the hyperconjugative interactions might explain some discrepancies in GIAO calculations.

Silica-based rigid monoliths exhibiting a trimodal hierarchical pore system have been successfully prepared through coating of a ceramic foam (CF) with sub-micro-/nanometric mesoporous particles (as building blocks). We have selected a bimodal porous silica, denoted as UVM-7 (a nanometric version of the well-known MCM-41 materials), consisting of small aggregates of nanometric surfactant-assisted mesoporous particles. A colloidal suspension of this material in water is used to coat through successive impregnation cycles the CF surface. The small intraparticle mesopore system (with pore diameters around 2−3 nm) is due to the supramolecular templating effect of the surfactant. Textural large-mesopores/macropores (in the 20−70 nm range) have their origin in the interparticle UVM-7 voids. The large macrocellular macropores are due to the CF support. The resulting monoliths present a good and homogeneous coverage level. Moreover, these composites display better mechanic properties than those of related silica ...

ZnO?SiO2 lamellar nanocomposites with high zinc content (5?Si/Zn?50) have been synthesized through a one-pot surfactant-assisted procedure from aqueous solution and starting from molecular atrane complexes of Zn and Si as inorganic hydrolytic precursors. This approach allows optimization of the dispersion of the ZnO nanodomains in the silica sheets. The nature of the layered silica materials has been confirmed by x-ray diffraction. Spectroscopic (ultraviolet?visible and photoluminescence) study of these layered silica materials shows that, regardless of the Si/Zn ratio, Zn atoms are organized in well-dispersed, uniform ZnO nanodomains (about 1.2?nm) partially embedded within the silica sheets. Quantum confinement effects have been observed in the optical response of the ZnO nanoparticles included in these nanocomposites.

Silica-based nanoparticulated bimodal mesoporous materials with high Zr content (43 ≥ Si/Zr ≥ 4) have been synthesized by a one-pot surfactant-assisted procedure from a hydroalcoholic medium using a cationic surfactant (CTMABr = cetyltrimethylammonium bromide) as structure-directing agent, and starting from molecular atrane complexes of Zr and Si as hydrolytic inorganic precursors. This preparative technique allows optimization of the dispersion of the Zr guest species in the silica walls. The bimodal mesoporous nature of the final high surface area nano-sized materials is confirmed by XRD, TEM, and N2 adsorption–desorption isotherms. The small intraparticle mesopore system (with pore sizes around 2–3 nm) is due to the supramolecular templating effect of the surfactant, while the large mesopores (around 12–24 nm) have their origin in the packing voids generated by aggregation of the primary nanometric mesoporous particles. The basicity of the reaction medium seems to be a key parameter in the definition of this last pore system. The effects induced by the progressive incorporation of Zr atoms on the mesostructure have been examined, and the local environment of the Zr sites in the framework has been investigated by UV/Vis spectroscopy. Observations based on the consequences of post-treatments of the as-synthesized materials with HCl/ethanol mixtures corroborate that the atrane method leads to Zr-rich materials showing enhanced site accessibility and high chemical homogeneity throughout the pore walls. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Nanoparticulate bimodal porous silica-based materials have been prepared through a surfactant-assisted procedure by using a simple template and starting from inexpensive sodium silicate as silicon source. Different procedural variables, such as pH or the nature and concentration of the surfactant, have been explored to optimize the preparative protocol, which allows, in turn, improved understanding of the formation process. The final bulk materials (called UVM-10 or M-UVM-10) are formed by pseudomorphic transformation of fresh silica-based xerogels under mild basic conditions. The UVM-10 architecture is constructed from small mesoporous nanoparticles, the aggregation of which generates a disordered secondary 3 D pore system (large-meso/macropores) defined by interparticle voids. Modulation of the intraparticle mesopore size is achieved by using surfactants with variable tail lengths, while maintaining the same head group. Textural porosity has been handled independently by hydrothermally modifying the particle size of the reactive silica-based xerogel. By simply adding metal alkoxides to the initial reaction mixture, the preparative protocol allows for functionalizing the silica walls by incorporating relatively high proportions of homogeneously dispersed heteroelements, such as Al and Ti.

Porous pure and doped silicas with pore sizes at two length scales (meso/macroporous) have been prepared through a large scale one-pot surfactant assisted reproducible procedure by using a simple template agent and starting from non-expensive sodium silicate as silicon source. Together with the relative low-cost of the reagents we have used, the simplicity of this method, which moreover is scalable and provides high yields, could be a strong argument for considering its suitability for the production of bimodal porous silicas. Additionally, we present a simple chemical scheme that allows directing the synthesis towards different related materials including both bimodal nanoparticulated mesoporous materials and unimodal particulate silica gels or MCM-41-like solids.

The use of triethanolamine containing complexes of Si and Mn as hydrolytic precursors allows the synthesis of doped mesoporous silicas in which the Mn content can be modulated up to reach a minimum value of the Si/Mn molar ratio of 3. This limit value corresponds to a Mn relative content significantly higher than those reported to date for similar materials (Si/Mn = 6). According to XRD, TEM and porosity data, the mesoporous nature typical of the MCM-41 silicas is retained even for the samples having the highest Mn content.

The synthesis of a new macrocyclic receptor (L 4 ) containing two 3,5-dimethylpyrazole units connected by dipropylenetriamine bridges is reported for the first time; pH-metric titrations indicate that L 4 shows six protonation steps in the pH range 2-11. In the absence of metal ions, the pyrazole moieties are not involved in acid-base processes in this pH range. Addition of Cu I I and Zn I I results in deprotonation of the pyrazole moieties which act as bis(monodentate) η 1 :η 1 ligands. This induced deprotonation occurs at higher pH values than in the complexes of the analogous ligand containing diethylenetriamine bridges (L 1 ). The crystal structures of [Cu 2 (H - 2 L 4 )](ClO 4 ) 2 and [Zn 2 (H - 2 L 4 )](ClO 4 ) 2 obtained by treatment of Na 2 [H - 2 L 4 ) with either Cu(ClO 4 ) 2 .6H 2 O or Zn(ClO 4 ) 2 .6H 2 O in methanol followed by recrystallisation from water/methanol also show the deprotonation of the pyrazole moieties. The coordination geometry around each metal ion is square-pyramidal and involves all nitrogen atoms of the macrocycle. The crystal structure of [Zn 2 (H - 2 L 1 )](ClO 4 ) 2 shows full involvement of all the nitrogen atoms of the macrocycle in the coordination to the metal ions. The coordination geometry can be defined as midway between a square pyramid and an irregular trigonal bipyramid. Treatment of neutral L 4 in methanol with Cu(ClO 4 ) 2 .6H 2 O yields a blue complex which, after heating in boiling water, crystallises as a red compound. Elemental microanalyses, ESI-MS and FAB-MS data of both forms of this complex are consistent with the formula [Cu 2 L 4 ](ClO 4 ) 4 .2H 2 O. Furthermore, these data along with the paramagnetic 1 H NMR spectrum of the red form of the compound suggest a structure in which the pyrazole rings are deprotonated while the central nitrogen atoms of the bridging chains are protonated and consequently uncoordinated. The change from the blue (square-pyramidal) to the red form (square-planar) can be ascribed to dissociation of the water molecules which occupy the axial positions in the Cu I I coordination spheres of the blue form. The variation of the magnetic susceptibility of the red complex [Cu 2 L 4 ]-(ClO 4 ) 4 .2H 2 O and the complex [Cu 2 (H - 2 L 4 )](ClO 4 ) 2 with temperature has been studied in the 2-300 K temperature range. Fitting of the experimental data provides J values which are among the highest found for doubly pyrazolate-bridged dicopper(n) complexes {J = -299 cm - 1 for red-[Cu 2 L 4 ](ClO 4 ) 4 .2H 2 O and J = -286 cm - 1 for [Cu 2 (H - 2 L 4 )]-(ClO 4 ) 2 }. A trinuclear Cull complex of formula [Cu 3 -(H - 2 L 4 )](ClO 4 ) 4 .2MeOH was also isolated after treatment of L 4 with Cu(ClO 4 ) 2 .6H 2 O solutions of higher concentration.

Pure mesoporous aluminum phosphonates and diphosphonates have been synthesized through an S+I- surfactant-assisted cooperative mechanism by means of a one-pot preparative procedure from aqueous solution and starting from aluminum atrane complexes and phosphonic and/or diphosphonic acids. A soft chemical extraction procedure allows opening the pore system of the parent mesostructured materials by exchanging the surfactant without mesostructure collapse. The hybrid nature of the pore wall can be modulated continuously from organic-free mesoporous aluminum phosphates (ALPOs) up to total incorporation of organophosphorus entities (mesoporous phosphonates and diphosphonates). The organic functional groups become basically attached to the pore surface or inserted into the ALPO framework (homogeneously distributed along the surface and inner pore walls) depending on the use of phosphonic or diphosphonic acids, respectively. X-ray powder diffraction, transmission electron microscopy, and surface analysis techniqu...

Silica-based MCM-41-like mesoporous materials with high cobalt content (∞ ≥ Si/Co ≥ 23) have been synthesized through a one-pot surfactant-assisted procedure from aqueous solution using a cationic surfactant (CTMABr = cetyltrimethylammonium bromide) as structural directing agent, and starting from molecular atrane complexes of Co and Si as inorganic hydrolytic precursors. This preparative technique allows optimizing the dispersion of the Co guest species in the silica walls. The mesoporous nature of the final materials is confirmed by XRD, TEM, and N2 adsorption−desorption isotherms. They display unimodal and relatively narrow pore size distributions, whereas their pore array evolves from ordered hexagonal (H0) to wormhole-like (W) as the Co content increases. A careful spectroscopic (UV−visible and NMR) and magnetic study of these materials shows that, regardless of the Si/Co ratio, Co atoms are organized in well-dispersed, uniform CoO nanodomains (ca. 3 nm) partially embedded within the silica walls. Th...

Organophosphorus moieties have been incorporated into mesoporous ALPOs through a one-pot surfactant-assisted procedure leading, for the first time, to periodic mesoporous aluminium phosphonates and diphosphonates. The number of organic groups on the surface or in the network can be modulated continuously up to the maximum incorporation level of the respective organophosphorus entities (100 %). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Superparamagnetic CoO-MCM-41 mesoporous nanocomposites, with variable cobalt amounts, in the form of well-dispersed CoO-like clusters, were prepared in a large compositional range by a one-step reproducible procedure employing co-hydrolysis and co-condensation of the inorganic precursors in a water/triethanolamine medium. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

The synthesis and coordination chemistry of the novel pyridine-functionalized ligand 2,6,9,12,16-pentaaza[17]-(2,6)pyridinophane (L1) is described. The compound behaves as a hexaprotic base in aqueous solution. NMR studies indicate a protonation pattern in which the sp2 pyridine nitrogen (N(py)) does not undergo a net protonation although it is involved in formation of hydrogen bonds. L1 forms mono and binuclear hydroxylated complexes. The crystal structure of [CuL1](ClO4)2 shows a square planar coordination for Cu2+ with the pyridine and the three central nitrogens of the chain forming the vertices of the square. The benzylic nitrogens could be occupying the axial positions of a strongly axially asymmetrically elongated octahedron. The kinetic data show that decomposition of the [Cu(HL1)]3+, [Cu(L1)]2+ and [Cu2(L1)(OH)]3+ complexes takes place in two steps the slower one being ascribed to the dissociation of the Cu–N(py) bond.

A diversity of zirconium-containing porous silicas of the MCM-41 type (Zr−MCM-41, ∞ ≥ Si/Zr ≥ 0.33) has been synthesized from aqueous solution using a cationic surfactant (CTABr = cetyltrimethylammonium bromide) as the structural directing agent, and starting from molecular atrane complexes of Zr and Si as precursors. Atrane inertness toward hydrolysis allows harmonization of the reactivity of the Zr and Si species, which in turn avoids subsequent phase segregation and results in chemically very homogeneous materials. Materials characterization by XRD, TEM, and N2 adsorption−desorption isotherms shows that all the prepared Zr−MCM-41 solids have high surface area and unimodal narrow pore size distribution, whereas their pore packing motives range from ordered hexagonal to wormhole-like arrays depending on the Zr content. The study of the local environment of the Zr atoms in these solids has been approached by means of spectroscopic techniques (IR, UV−vis, and NMR).

Several novel metal-quinolone compounds have been synthesized and characterized by analytical, spectroscopic and X-ray diffraction methods. The crystal structure of the four compounds, Na(2)[(Cd(Cx)3)(Cd(Cx)3(H2O))].12H2O, [Co(Cp)2(H2O)2].9H2O, [Zn(Cp)2(H2O)2].8H2O and [Cd(HCp)2(Cl)2].4H2O, is presented and discussed: HCx=1-ethyl-1,4-dihydro-4-oxo(1,3)-dioxolo(4,5-g)cinnoline-3-carboxylic acid and HCp=1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid. In all these compounds the quinolone acts as a bidentate chelate ligand that binds through one carboxylate oxygen atom and the exocyclic carbonyl oxygen atom. Complexes of ciprofloxacin were screened for their activity against several bacteria, showing activity similar to that of the ligand. In addition, the number of bacteria killed after 3 h of incubation with the ligand, [Co(Cp)2(H2O)2].9H2O, Ni(Cp)2.10H2O and Cu(Cp)2.6H2O, was determined against S. aureus ATCC25923. There is a direct relationship between the growth rate and the lethal rate. Against growing bacteria, the ligand is the most bactericidal and Cu(Cp)2.6H2O is the less bactericidal. On the contrary, against non-dividing bacteria, the complexes were more bactericidal than the ligand, with Cu(Cp)(2).6H(2)O the most bactericidal compound.

A new simple method for obtaining the intermediate ribbonlike SBA-8 mesoporous silica is presented and discussed. We show how the SBA-8 phase can be prepared with the help of commercial alkyltrimethylammonium nonrigid surfactants (such as cetyltrimethylammonium bromide) instead of rigid bolaform amphiphiles, which were used as templates in the only SBA-8 synthesis procedure previously reported. The method is based on the use of atrane complexes as silicon precursors, and we also show how bringing into play fundamental kinetic parameters (like reaction time and temperature at which the successive reaction steps are carried out) makes it possible to modulate the resulting material topology.

The reaction of poly(dimethylsilane) (PDMS) and poly(dimethylcarbosilane) (PCS) with bis(cyclopentadienyl)M dichloride Cp2MCl2 (M ) Ti, Zr, Hf) complexes has been used as a new route to obtain ceramic materials based on SiC-containing M. The reaction is completed at a relatively low temperature, 900 °C, yielding the corresponding amorphous SiC/MC ceramics which have been characterized by means of 29 Si MAS NMR. These amorphous materials have been treated at higher temperatures, 1350 °C, under a purified argon atmosphere, yielding partially crystallized products which have been studied by X-ray powder diffraction and 29 Si MAS NMR. The effect of the composition of the mixture of precursors is

The interaction with Cu2+ and dopamine of three polyazacyclophanes containing pyrazole fragments as spacers is described. Formation of mixed complexes Cu2+-macrocycle-dopamine has been studied by potentiometric methods in aqueous solution. The crystal structures of the complexes [Cu2(L1)(H2O)2](ClO4)4*2H2O (4) (L1 = 13,26-dibenzyl-3,6,9,12,13,16,19,22,25,26-decaazatricyclo[22.2.1.1(11,14)]octacosa-1(27),11,14(28),24-tetraene) and [Cu2(H-1L3)](HClO4)(ClO4)2*2H2O (6) (L3 = 1,4,7,8,11,14,17,20,21,24,29,32,33,36-tetradecaazapentacyclo[12.12.12.1(6,9).1(19,22).1(31,34)]hentetraconta-6,9(41),19(40),21,31,34(39)-hexaene) are presented. In the first one (4), each Cu2+ coordination site is made up by the three nitrogens of the polyamine bridge, a sp2 pyrazole nitrogen and one water molecule that occupies the axial position of a square pyramid. The distance between the copper ions is 6.788(2) A. In the crystal structure of 6, the coordination geometry around each Cu2+ is square pyramidal with its base being formed by two secondary nitrogens of the bridge and two nitrogen atoms of two different pyrazolate units which act as exobidentate ligands. The axial positions are occupied by the bridgehead nitrogen atoms; the elongation is more pronounced in one of the two sites [Cu(1)-N(1), 2.29(2) A; Cu(2)-N(6), 2.40(1) A]. The Cu-N distances involving the deprotonated pyrazole moieties are significantly shorter than those of the secondary nitrogens. The Cu(1)...Cu(2) distance is 3.960(3) A. The pyrazole in the noncoordinating bridge does not deprotonate and lies to one side of the macrocyclic cavity. One of the aliphatic nitrogens of this bridge is protonated and hydrogen bonded to a water molecule, which is further connected to the sp2 nitrogen of the pyrazole moiety through a hydrogen bond. The solution studies reveal a ready deprotonation of the pyrazole units induced by coordination to Cu2+. In the case of L2 (L2 = 3,6,9,12,13,16,19,22,25,26-decaazatricyclo[22.2.1.1(11,14)]octacosa-1(27),11,14(28),24-tetraene), deprotonation of both pyrazole subunits is already observed at pH ca. 4 for 2:1 Cu2+:L2 molar ratios. All three free receptors interact with dopamine in aqueous solution. L3 is a receptor particularly interesting with respect to the values of the interaction constants over five logarithmic units at neutral pH, which might suggest an encapsulation of dopamine in the macrocyclic cage. All three receptors form mixed complexes Cu2+-L-dopamine. The affinity for the formation of ternary dopamine complexes is particularly high in the case of the binuclear Cu2+ complexes of the 1-benzyl derivative L1.

The interaction of copper (II), zinc(II) and cadmium(II) with Trimethoprim (2,4-diamino-5-(3',4',5'-trimethoxybenzyl) pyrimidine) has been studied. The crystal structures of [Zn(Trim)2Cl2] (2) and [Cd(Trim)Cl2(CH3OH)]n (4) are reported. Compound (2) exhibits a distorted tetrahedral environment around the metal center and crystallizes in the triclinic space group P1 with a=10.2397(6), b=10.4500(6), c=16.3336(16) A, alpha=96.141(8), beta=106.085(5), gamma=96.551(5) degrees and Z=2. In complex (4), the Cd(II) centers are bridged sequentially by two chlorine ions to form infinite chains and present a six-coordinated environment; the compound crystallizes in the monoclinic P2(1)/C space group with a=13.958(5), b=7.532(2), c=18.390(2) A, alpha=90, beta=97.32(5), gamma=90 degrees and Z=4. In both structures the Trimethoprim acts as a monodentate ligand through the pyrimidinic nitrogen N(1) atom. The characterization of the Cu(Trim)2(CH3O)(ClO4) complex through EPR and magnetic measurements suggests a binuclear or polinuclear nature, with bridging methoxo groups. The complexes were screened for their activity against several bacteria, showing activity similar to that of trimethoprim.

A new simple and versatile technique to obtain mesoporous oxides is presented. While implying surfactant-assisted formation of mesostructured intermediates, the original chemical contribution of this approach lies in the use of atrane complexes as precursors. Without prejudice to their inherent unstability in aqueous solution, the atranes show a marked inertness towards hydrolysis. Bringing kinetic factors into play, it becomes possible to control the processes involved in the formation of the surfactant–inorganic phase composite micelles, which constitute the elemental building blocks of the mesostructures. Independent of the starting compositional complexity, both the mesostructured intermediates and the final mesoporous materials are chemically homogeneous. The final ordered mesoporous materials are thermally stable and show unimodal porosity, as well as homogeneous microstructure and texture. Examples of materials synthesised on account of the versatility of this new method, including siliceous, non siliceous and mixed oxides, are presented and discussed.

The preparation and interaction of the new polyaza[n]naphthalenophanes 2,5,8,11-tetraaza[12](1,4)naphthalenophane (L1) and 2,6,9,13-tetraaza[14](1,4)naphthalenophane (L2) with hydrogen ions and Cu2+ is described. The crystal structure of the new tetranuclear copper(II) complex [Cu4(L1)2(OH)4Cl2(H2O)2]2(H3O2)(ClO4)2Cl·2H2O (L1=2,5,8,11-tetraaza[12](1,4)naphthalenophane) is presented and discussed. A variety of intra- and intermolecular forces contribute to the particular organisation of the crystal. The solution studies indicate the formation of similar tetranuclear species for L1 while for L2 just mononuclear 1:1 species are detected.

The interaction of PtCl42− with the new azaparacyclophane 2,5,8,11-tetraaza[12]paracyclophane (L2) has been studied by 1H, 13C and 195Pt NMR spectroscopy. Three different complexes are detected as a function of pH, all of them presenting cis-arrangement of nitrogen donors and chloride anions. In the first one, formed at acidic pH, the central nitrogen atoms of the macrocyclic are coordinating to Pt(II) while the benzylic nitrogens remain protonated. Deprotonation of these nitrogens brings about a reorganisation of the complex, and the platinum is then coordinated by one benzylic nitrogen and the consecutive nitrogen in the macrocycle. This process can be monitored by NMR. Finally, addition of a second mol of PtCl42− for each mole of L2 causes, most likely, the formation of a binuclear complex in which the tetrammine chain behaves as two ethylenediamine subunits. The crystal structure of the adduct [PtBr4]2[H4L1] has been solved by X-ray diffraction analysis (space group P21/c, a = 8.092(2), b = 16.049(2), c = 21.783(3) A, α = 90.00(1), β = 100.34(2), γ = 90.00(1), Z = 4, R1 = 0.0528, wR2 = 0.1612). The compound is held together mainly through coulombic interactions between the charged polyammonium groups of the macrocycle and the PtBr42− anions aswell as through an extensive hydrogen bond network in which participate the bromides of the two PtBr42− anions and a lattice water molecule.

The interaction of cobalt(II), nickel(II), copper(II), and zinc(II) with Cinoxacin (HCx = 1-ethyl-1,4-dihydro-4-oxo(1,3)dioxolo(4,5-g)cinnoline-3-carboxylic acid), a 4-quinolone derivative, has been studied at metal/ligand ratios of 1:1-1:3 by means of pH-metric, spectrophotometric, and ESR methods. The formation constants have been determined and the stereochemistry for the metal ions in the species present in aqueous solutions (at 37 ± 0.1°C and I = 0.1 mol dm −3 NaCl) is discussed. In all the studied systems, complexes with different stoichiometric ratios, in which cinoxacin acts both as neutral and deprotonated ligand, are formed. The anomalous sequence of the stepwise stability constants observed for cobalt(II) and nickel(II) systems suggests changes in stereochemistry when CoCx 2 and NiCx 2 are formed. For zinc(II) this change has to be still more pronounced since a [ZnCx] + species has not been detected. For the Cu(II) system the sequence in the stepwise stability constants indicates the preferential formation of the [CuCx] + monocomplex. The crystal and molecular structure of new Cu(II) and Ni(II) complexes of cinoxacin have been investigated. The metal ion in [Cu(Cx) 2 H 2 O]·3H 2 O is five-coordinated and the complex crystallizes in the triclinic P 1 space group with a = 10.620(1), b = 11.358(1), c = 12.440(2) A , α = 78.25(1), β = 80.24(1), γ = 63.34(1)°, and Z = 2 . The complex [Ni(Cx) 2 -(DMSO) 2 ]·4H 2 O contains six-coordinated Ni(II) and crystallizes in the triclinic P 1 space group with a = 8.866(3), b = 9.141(1), c = 11.580(1) A , α = 69.301(9), β = 82.17(2), γ = 75.86(2)°, and Z = 1 .

The preparation, spectroscopic, magnetic properties, and crystal structure of [Cu(stzxpy) 3 Cl] (stz − stands for the deprotonated form of sulfathiazole, 4-amino-N-2-thiazolylbencenosulfonamide) are reported. Crystals are orthorhombic, space group Pbca, with cell constants a = 15.834(2), b = 17.512(4), and c = 18.79(2) A, and Z = 8. The structure was solved and refined to R = 0.041 (R W = 0.040). The structure consists of mononuclear units linked via hydrogen bonds to form the tridimensional pyramid. The geometry of CuN3N*NCl chromophore is distorted square-pyramid. The superoxide-dismutase mimetic activity of the compound is measured and compared with those of the SOD enzyme, the free drug, and other related sulfathiazole complexes.

The reaction of [Rh2(μ2-O2CCH3)3{μ2-(C6H4)PMePh}] (1) in CHCl3 with one mole of PPh3 gives the two phosphine monoadducts, which are in rapid equilibrium above −40 °C. After 6 h at room temperature this mixture gives [Rh2(μ2-O2CCH32{μ2-(C6H4)PMePh}{μ2-(C6H4)PPh2}](HO2CCH3)2 (3), a doubly metalated compound with a head-to-head configuration. 1 reacts with two moles of PPh3, forming the bis-adduct 1.P2, which at 10 °C gives a mixture 3, in the form of its phosphine adduct 3.P, and [Rh2(μ2-O2CCH3)2{μ2-(CH2)PPh2}{μ2- (C6H4) PPh2}(PPh3)] (2). It is confirmed that 3.P is not the kinetic product in the reaction from 1.P2 to 2. The structure of [Rh2(μ2-O2CCH3)2{μ2-(CH2)PPh2}{μ2-(CP6H4) PPh2} (PPh3)]·2CH2Cl2 has been determined by X-ray diffraction: Mr = 1216.55, monoclinic, space group P21/c, a=19.930(8), b=15.29(2), c=16.84(2) A, β=90.14(9)°, V=5129(9) A3, Z=4, Dc=1.58 g cm−3, Mo Kα radiation (graphite monochromator, λ=0.71073 A), μ (Mo Kα)=9.80 cm−1, F(000)=2464, T=200 K. The final conventional R factor was 0.061 for 4749 ‘observed’ reflections. The compound contains an orthometalated triphenylphosphine and a diphenylphosphinomethanide group bridging the two rhodium atoms. The two ligands are in a head-to-head configuration. Two bridging acetate groups and one axial PPh3 complete the coordination around the rhodium atoms. The RhRh bond distance is 2.532(2) A.

Stepwise exchange reactions of acetate groups by trifluoroacetate groups have been observed for [Rh2(O2CMe)3{(C6H4)PPh2}]·2MeCO2H 1, in CDCl3–CF3CO2H at room temperature. The first reaction involves a fast exchange of the two axial molecules of acetic acid as well as the acetate group trans to the metallated phosphine. In a second step the exchange of one acetate group cis to the metallated phosphine occurs. The exchange of the second cis acetate group yielding [Rh2(O2CCF3)3{(C6H4)PPh2}]·2CF3CO2H 3, has been studied by 1H NMR spectroscopy. This exchange follows a rate equation which is dependent on the concentration of trifluoroacetic acid used, kobs=(k1+k2[CF3CO2H]½[Rh2]. The partially deuteriated compound [Rh2(O2CCF3)3{(C6D4)P(C6D5)2}]·2CF3CO2H 3D in the presence of trifluoroacetic acid undergoes D–H exchange at the ortho positions of the phenyl rings of the phosphine. This exchange has been studied at 318 K. The observed D–H exchange is explained by an electrophilic attack at the rhodium–carbon bond by the trifluoroacetic acid, which produces protonation of the ortho aromatic carbon atom, and subsequent demetallation followed by a reverse metallation reaction. An X-ray crystal structure determination of compound 3 has been carried out: space group P21/n(monoclinic), a= 12.369(2), b= 21.711 (6), c= 13.367(2), β= 90.11 (2)°, Z= 4 and R= 0.044. It contains three trifluoroacetate groups bridging a Rh24+ unit which has a Rh–Rh bond distance of 2.438(1)A; the fourth bridging ligand is a triphenylphosphine metallated at one of the ortho positions. Two molecules of trifluoroacetic acid occupy the axial positions.

We present here a new family of bimodal porous silicas with organically modified surfaces or frameworks constructed from mesoporous primary nanoparticles. These new organosilicas, denoted HPNOs, have been synthesized through a one-pot surfactant-assisted procedure by using a simple commercial template agent in triethanolamine/water media.