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Argania spinosa (L.) Skeels, an endemic Moroccan plant species from the Sapotaceae family, holds significant ecological, pharmaceutical, and socioeconomic value in the arid mid-western region. However, it is facing rapid degradation. Therefore, understanding its genetic diversity is critical for preserving this national heritage. We sequenced, assembled, and annotated the mitochondrial genome of A. spinosa and compared it to other plants in the Ericales order. Mitochondrial-like sequences from the A. spinosa genome were assembled using GetOrganelle, resulting in a 707,441 base pair mitochondrial genome with 45.75 % GC content. Annotation identified 32 protein-coding genes, 16 transfer RNAs, and 2 ribosomal RNA genes. Phylogenetic analysis of 15 Ericales species affirms that A. spinosa is closely related to the Theaceae family, which is in accordance with results from the chloroplast genome.

Unlike virtual classrooms that have received extensive research attention in both academic and practical contexts because of their ability to improve students’ outcomes, the use of advance organizers are still in need for more research to prove their efficacy in fulfilling expected learning outcomes in these virtual classrooms. Hence, the present study aims to identify the impact of using such organizers in virtual classrooms on the development of students’ integrated science process skills. The present study was applied to 64 students who were studying for their Master’s degree in the vocational education techniques in the ”Research Project” course. Participants were randomly divided into two equal experimental groups with 32 students in each. An assessment card of five main domains was used to evaluate students’ skills in research procedural definition, identification and control of the research variables, questions and/or hypotheses, procedures and experimentation besides research interpretation of the results. Data analysis showed that the use of advance organizers in virtual classes was of great effect on the development of participants’ integrated science process skills because skills of students in the first experimental group were better mastered than the skills of their peers in the second experimental group in accordance with the subskills in the five domains.

The present work aimed to study the feasibility of photo-Fenton oxidation for the degradation of chlortetracycline chlorhydrate (CTC) in aqueous solutions, as well as the modelling of system behaviour by artificial neural networks. The removal performance of CTC oxidation by the Photo-Fenton process was studied under solar radiation. Different parameters were studied, such as pH (3 to 5), and initial concentrations of CTC (0.1 to 10 mg l–1), hydrogen peroxide (1.701 to 190.478 mg l–1), and ferrous ions (2.8 to 103.6 mg l–1). Results showed that a high removal efficiency of 92 % was achieved at pH 3 under optimised conditions, such as 10 mg l–1 of CTC, 127.552 mg l–1 of H2O2, and 36.4 mg l–1 of Fe2+. The transformation of CTC molecules was proved by UV-visible and HPLC analyses, which showed that almost no CTC molecules were remaining in the treated solution. A multi-layer perceptron artificial neural network has been developed to predict the experimental removal efficiency of CTC based on four dimensionless inputs: molecular weight, and initial concentrations of CTC, hydrogen peroxide and ferrous ions. The best network has been found with a high determination coefficient of 0.9960, and with a very acceptable root mean square error 0.0108. In addition, the global sensitivity analysis confirms that the most influential parameter for the CTC removal by photo-Fenton oxidation is the initial concentration of ferrous cations with a relative importance of 33 %.

Introduction: A deep understanding of physiology, physiopathology, pharmacology, and the management of pain is crucial for nurse anaesthetists to ensure the well-being of their patients. Thus, the teaching strategies should enhance the transition from acquiring the fundamental pain phenomena, to developing translational and critical thinking. The aim of the study is to determine if the flipped classroom that is considered an active learning approach is most effective compared to the traditional method in teaching pain management and if it improves students' academic performance. Methods: This study was quasi experimental, at a higher institute of nursing professions, among third-year anaesthesia resuscitation nursing students. participants were randomly allocated into either: the flipped classroom group where PBL was used (FG, n = 19), or the traditional lecture-based classroom group (TG, n = 19). The results and impact of the above approach were appreciated via the analysis of the summative assessment of the class group and from the questionnaire submitted to students. Results: The present study revealed that in the midterm exam, the mean score of the flipped classroom group (14.0) which is significantly higher (p

The learning management system is a digital environment that enables the tracking of learner activities, allowing special forms of data from the academic context to be explored and used to enhance the learning process. This study aims to identify the effect of using big data technology in digital environments on the development of electronic social competence among optimal investment diploma students. An experimental method was used to explore the effect of big data technologies usage on social competence. The sample for this study consisted of (120) students in the Department of Curriculum and Teaching Methods, divided into two equal groups through random selection. The first group studied the course through a digital environment with the use of big data technology, while the second group studied the course through the digital environment without using big data technology. The electronic social competence scale was further utilized as a tool to meet the study’s goal. The experimental findings showed that big data technologies in the used digital environment significantly improved the electronic social competence of Optimal Investment Diploma students (personal skills, self-management skills, and academic skills). The results provide significant proof of the advantages of big data technology in social competence studies and development.

The predictability of the adsorption capacity of the multicomponent adsorption system was modelled using Support Vector Machine (SVM). Two SVM models were built and compared. In the first model, the SVM method was used with an already built-in optimisation algorithm. However, in the second model, the SVM method was used by means of a very recent and efficient optimisation algorithm: the Dragonfly Algorithm (DA). The models’ accuracy was evaluated by three well-established statistical metrics (root mean squared error RMSE, determination coefficient R2, and correlation coefficient R). The used data were collected from previous experimental papers published in literature containing all kinds of pollutants, such as heavy metal ions, dyes, and organic compounds, and different natural/synthetic adsorbents. The dataset contained five important variables with 1023 points; the variables were divided into four inputs (molecular weight, equilibrium concentrations of adsorbate, specific area of adsorbent, and temperature), and one output (adsorption capacity at equilibrium). The data were divided using the holdout function into two subsets (80 % for training set, and 20 % for test set). The programming stage was carried out using MATLAB software. The results showed that the optimised DA-SVM model with RBF-Gaussian kernel function had good ability for global search combined with high prediction accuracy, with R2 = 0.997, R = 0.998, and RMSE = 2.539. The obtained model can be used to predict the efficiency of the adsorption system, and provides a tool for process optimisation responding to changes in operating conditions. A new graphical user interface (GUI) was developed with MATLAB GUI to estimate accurately the desired responses by using the best DA-SVM model.

Knowledge of mechanisms by which large mammals select rubbing trees (RT) is a major challenge for the effective management of forests and wildlife resources. In this study, we investigated this issue regarding the Wild boar (Sus scrofa) in the Moroccan forested site of Sidi Boughaba as a case study. We used data from four sets of variables, namely topography, forest type, landscape composition, and microhabitat, measured at 58 rub and control trees, to determine the factors associated with the occurrence of RT by means of generalized linear mixed models. Our results showed that the RT occurrence increased with a high density of red juniper trees and declined with distance to the nearest footpath. Variation partitioning analysis revealed that the pure fraction of microhabitat was the most robust in explaining this occurrence (adj. R2 = 0.17, P < 0.001), followed by that of forest type (adj. R2 = 0.05, P < 0.05). A scientific monitoring system must be set up to strike a balance between the availability of forest trees on the one hand and the pressure exerted by wild boars on this internationally importance site on the other. It is imperative to test the geographical generality of our results in other Mediterranean forests.

Abstract Synechococcus are unicellular cyanobacteria susceptible to environmental fluctuations and can be used as bioindicators of eutrophication in marine ecosystems. We examined their distribution in two Moroccan lagoons, Marchica on the Mediterranean coast and Oualidia on the Atlantic, in the summers of 2014 and 2015 using 16S rRNA amplicon oligotyping. Synechococcus representatives recruited a higher number of reads from the 16S rRNA in Marchica in comparison to Oualidia. We identified 31 Synechococcus oligotypes that clustered into 10 clades with different distribution patterns. The Synechococcus community was mainly represented by oligotype 1 (clade III) in Marchica. Cooccurring clades IV and I had an important relative abundance in Marchica in the summer of 2014, which is unusual, as these clades are widespread in cold waters. Moreover, Clades VII and subcluster “5.3” formed a sizeable percentage of the Synechococcus community in Marchica. Notably, we found low Synechococcus sequence counts in the Atlantic Lagoon. These results showed that the relative abundance of Synechococcus reads is not constant over space and time and that rare members of the Synechococcus community did not follow a consistent pattern. Further studies are required to decipher Synechococcus dynamics and the impact of environmental parameters on their spatial and temporal distributions.

Modern approaches in education technology, which make use of advanced resources such as electronic books, infographics, and mobile applications, are progressing to improve education quality and learning levels, especially during the spread of the coronavirus, which resulted in the closure of schools, universities, and all educational facilities. To adapt to new developments, students’ performance must be tracked in order to closely monitor all unfavorable barriers that may affect their academic progress. Educational data mining (EDM) is one of the most popular methods for predicting a student’s performance. It helps monitoring and improving students’ results. Therefore, in the current study, a model has been developed so that students can be informed about the results of the computer networks course in the middle of the second semester and 11 machine algorithms (out of five classes). A questionnaire was used to determine the effectiveness of using infographics for teaching a computer networks course, as the results proved the effectiveness of infographics as a technique for teaching computer networks. The Moodle (Modular Object-Oriented Dynamic Learning Environment) educational platform was used to present the course because of its distinctive characteristics that allow interaction between the student and the teacher, especially during the COVID-19 pandemic. In addition, the different methods of classification in data mining were used to determine the best practices used to predict students’ performance using the weka program, where the results proved the effectiveness of the true positive direction of functions, multilayer perceptron, random forest trees, random tree and supplied test set, f-measure algorithms are the best ways to categories.

The rapid and global spread of the novel coronavirus severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has raised serious public health concerns, including in Mauritania. We sequenced and analyzed the entire genome of 13 SARS-CoV-2 virus strains isolated from polymerase chain reaction (PCR)-positive symptomatic patients sampled from March 3 to May 31, 2021 to better understand SARS-CoV-2 introduction, propagation, and evolution in Mauritania. A phylogenetic tree using available data from the EpiCoV GISAID database and a variant network with non-Mauritanian sequences were constructed. Variant analysis of the 13 Mauritanian SARS-CoV-2 genome sequences indicated an average mutational percentage of 0.39, which is similar to that in other countries. Phylogenetic analysis revealed multiple spatiotemporal introductions, mainly from Europe (France, Belgium) and Africa (Senegal, Côte d’Ivoire), which also provided evidence of early community transmission. A total of 2 unique mutations, namely, NSP6_Q208K and NSP15_S273T, were detected in the NSP6 and NSP15 genes, respectively, confirming the aforementioned introduction of SARS-CoV-2 in Mauritania. These findings highlight the relevance of continuous genomic monitoring strategies for understanding virus transmission dynamics and acquiring knowledge to address forthcoming sources of infection in Africa.

The emergence of a novel coronavirus that later on rendered a global pandemic, caused desperation within the communities and drove increased interest in exploring medicinal plant–based therapeutics to treat and prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus infections. Many medicinal plants have been reported to have antiviral, anti-inflammatory, and immunomodulatory effects that hinder, cure, or ease the symptoms of COVID-19 infection. This exploratory study seeks to dock the active components of Cannabis sativa , a natural plant with several pharmacological and biological properties, with the angiotensin-converting enzyme II (ACE2) receptor. A total of 3 C. sativa active components have been found to bind to the ACE2 protein active site and could inhibit spike binding, although they do not compete directly with the receptor-binding domain (RBD) of SARS-CoV-2. 6-Prenylapigenin, cannabivarin (CBN-C3), and Δ8-tetrahydrocannabinolic acid-A (Δ8-THCA) have a greater affinity (−8.3, −8.3, and −8.0 kcal/mol, respectively) and satisfactory interaction with ACE2 than its inhibitor MLN-4760 (−7.1 kcal/mol). These potential drugs with higher affinity for the ACE2 receptor and adequate absorption, distribution, metabolism, excretion, and toxicity (ADMET) values are candidates for treating or preventing SARS-CoV-2 infections. In vitro and in vivo investigations are needed to evaluate further the efficacy and toxicity of these hit compounds.

The objective of this study was to model the removal efficiency of ternary adsorption system using feed-forward back propagation artificial neural network (FFBP-ANN). The ANN model was trained with Levenberg–Marquardt back propagation algorithm and the best model was found with the architecture of {9-11-4-3} neurons for the input layer, first and second hidden layers, and the output layer, respectively, based on two metrics, namely, mean squared error (MSE) = (0.2717–0.5445) and determination coefficient (R2) = (0.9997–0.9999). Results confirmed the robustness and the efficiency of the developed ANN model to model the adsorption process.

In many nations affected by the COVID-19 pandemic, the situation in higher education institutions has changed. During the pandemic, these institutions have introduced numerous e-solutions to continue the process of education. Besides, research has shown many benefits in the last years of MOOCs. Yet, to date there are few studies to explore some individual characteristics, such as learners’ metacognitive skills, that might have an impact on learning outcomes in MOOCs. Furthermore, promotion of deep learning is a serious challenge for online courses including MOOCs. Therefore, the purpose of this research was to explore the role of metacognition in promoting deep learning in MOOCs during COVID-19 pandemic. The participants were students at the department of home economics who were all at the seventh academic level. Based on their scores on the metacognition awareness inventory (MAI), they were divided into two experimental groups, i.e. high metacognition students and low metacognition students. A three- aspect assessment card of deep learning namely connecting concepts, creating new concepts, and critical thinking was used to collect data. The results showed that MOOC was more effective in fostering the deep learning aspects of high metacognition skills, and deep learning as a whole. With regard to backward seeking and slow watching events, results showed significant differences in favor of high metacognition students (HMs). Nevertheless, there were no statistically significant differences between students in both groups regarding the pausing event.

The increasing number of enlistees claiming their right to enroll in the programs of African Universities and the limited number of Higher Education Institutions (HEIs) were the prime reasons of students overcrowding in classes. Massive Open Online Courses (MOOCs) showed a potential to help limiting the challenges of massification in open access HEIs. As the literature review of the MOOC situation in Africa is still nascent, we will qualitatively share the experience of Cadi Ayyad University in Marrakech, Morocco (UCA) in launching a MOOC for its learners as a case study. Created in 2013, this MOOC was entitled UC@MOOC and appeared to respond to the challenges of massification in open access HEIs and the language difficulties faced by students. We will also present an overview of this project, its achievements and the quantity of knowledge delivery it accomplished. This MOOC experience attracted learners from other countries. And we have found that a shortage of MOOCs in Africa drove learners from other African francophone countries to learn from UC@MOOC. Yet a low-cost MOOC with certain limitations such as the weak ICT infrastructure available to the African public will thrive if operated using a MOOC platform and boosted its financial means.

BACKGROUND: The nursing module teaches basic nursing principles and procedures to undergraduate nursing students. This course is important for the acquisition of procedural and psychomotor skills. The aim of the present study is to evaluate the influence of blended training on the acquisition of practical skills related to gastric insertion tubes.MATERIALS AND METHODS: A quasi-experimental study was undertaken, containing three groups: The blended group benefited from e-learning, followed by simulation), while the two groups benefited from theoretical teaching and procedural simulation. Then, the degrees of acquisition of declarative and procedural knowledge and the time of completion were measured.RESULTS: The declarative knowledge grade was higher in the Simulation (16.07) and Blended (15.21) groups than in the Traditional Group (11.66), with a statistically significant difference (P < 0.001). The results also showed a statistically significant difference between the procedural knowledge grades of the three groups (P < 0.001). A statistically significant correlation was detected between declarative and procedural knowledge scores (r = 0.58, P < 0.001) and a negative correlation between procedural knowledge and the time of completion (r = -0.422, P < 0.001).CONCLUSIONS: The results of this experimentation confirm the positive effect of the blended learning approach on the acquisition of declarative and procedural knowledge as well as the time management allocated to teaching.

The COVID-19 pandemic and the draconian measures applied to limit its spread have accelerated the process of digitalizing many activities, including those within the health sector. In Morocco, a developing country in northern Africa, digital health has been deployed extensively, and in a remarkable way, to support the management of the current health crisis. Morocco is taking significant measures to become a key player in the process of achieving Sustainable Development Goals (SDG) goal 3. The government has comprehensively integrated digital technology throughout its coordinated containment and mitigation processes. These processes encompass testing and diagnostics; virus genomic surveillance; telecare of suspected and chronic patients; COVID-19 patient contact tracing and tracking; a laboratory information system for medical material dispatching, biological sample collection, and data processing nationwide; and smart vaccination management. Moreover, the pace of amending legislation for enabling efficient telemedicine practice has been achieved at a record-breaking. The successful implementation of all of these digital health strategies testify to the effectiveness of digitalization for managing the health aspects of the pandemic and for the future development of health systems in Morocco and in the African continent, where digital health and telemedicine is set to become the cornerstone of medical practice.

Open education is one of the most important settings in every society. It grants everyone the right to learn freely. Today, technology is helping to make learning even more open by providing an environment of online education, which plays a remarkable role in shortening distances and encouraging students to learn. At Cadi Ayyad University (UCA) the new-enrolled students are facing linguistics barriers as well as overcrowding in classrooms, in particular for those in open access institutions. Subsequently, they cannot have an easy access to their face-to-face courses. To help students to overcome these problems, the university has decided to design an online environment for all courses and programmes. The most innovative project adopted at UCA to face massification was inspired from the massive open online courses and was designed as an open Educational platform entitled UC@MOOC. More than 120 scripted courses have been posted online so far. In this paper we will describe and discuss an analytics research on geometrical optics course designed for around 2000 students at UCA. Through out this research we will explain how this initiative has been considered as a source of producing open educational resources.

Objective: To examine the association between surgeon gender and early postoperative complications, including 30-day death and readmission, in elective surgery., Background: Variations between male and female surgeon practice patterns may be a source of bias and gender inequality in the surgical field, perhaps impacting quality of care. However, there are limited and conflicting studies regarding the association between surgeon gender and postoperative outcomes., Methods: MEDLINE and Embase were searched in October 2023 for observational studies including patients who underwent elective surgery requiring general or regional anesthesia across multiple surgical specialties. Multiple independent blinded reviewers oversaw the data selection, extraction, and quality assessment according to the PRISMA, MOOSE, and Newcastle Ottawa Scale guidelines. Data were pooled as odds ratios, using a generic inverse-variance random-effects model., Results: Of 944 abstracts screened, 11 studies were included in this systematic review and meta-analysis. A total of 4,440,740 postoperative patients were assessed for a composite primary outcome of mortality, readmission, and other complications within 30 days of elective surgery, with a total of 325,712 (7.3%) surgeries performed by 7,072 (10.9%) female surgeons. There was no association between surgeon gender and the composite of mortality, readmission, and/or complications (odds ratio=0.97, 95% CI 0.95 to 1.00; I2=64.9%; P=0.001)., Conclusions: These results support that surgeon gender is not associated with early postoperative outcomes, including mortality, readmission, or other complications in elective surgery. These findings encourage patients, healthcare providers, and stakeholders not to consider surgeon gender as a risk factor for postoperative complications., Competing Interests: Disclosures: The authors have no financial disclosures or conflicts of interest to declare., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

The electrocatalytic oxidation of glycerol by metal electrocatalysts is an effective method of low-energy-input hydrogen production in membrane reactors in alkaline conditions. The aim of the present study is to examine the proof of concept for the gamma-radiolysis-assisted direct growth of monometallic gold and bimetallic gold-silver nanostructured particles. We revised the gamma radiolysis procedure to generate free-standing Au and Au-Ag nano- and micro-structured particles onto a gas diffusion electrode by the immersion of the substrate in the reaction mixture. The metal particles were synthesized by radiolysis on a flat carbon paper in the presence of capping agents. We have integrated different methods (SEM, EDX, XPS, XRD, ICP-OES, CV, and EIS) to examine in detail the as-synthesized materials and interrogate their electrocatalytic efficiency for glycerol oxidation under baseline conditions to establish a structure-performance relationship. The developed strategy can be easily extended to the synthesis by radiolysis of other types of ready-to-use metal electrocatalysts as advanced electrode materials for heterogeneous catalysis.

In this paper, we report the first synthesis and characterisations of bimetallic gold(i)-silver(i) calix[8]arene complexes. We show that the radiolytic reduction of these complexes leads to the formation of small bimetallic nanoparticles with an alloyed structure, as evidenced by XPS, HR-TEM and STEM/HAADF-EDX measurements., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Nanoformulated calix[8]arenes functionalized with N -heterocyclic carbene (NHC)-palladium complexes were found to be efficient nano-reactors for Suzuki-Miyaura cross-coupling reactions of water soluble iodo- and bromoaryl compounds with cyclic triol arylborates at low temperature in water without any organic co-solvent. Combined with an improved one-step synthesis of triol arylborates from boronic acid, this remarkably efficient new tool provided a variety of 4'-arylated phenylalanines and tyrosines in good yields at low catalyst loading with a wide functional group tolerance.

Benzyloxycalix[8]arene supported catalysts bearing N-heterocyclic carbene palladium complexes on each subunit were readily synthesized. Intermediates and catalysts were fully characterized, allowing for a fine control of their structure. X-ray diffraction analysis confirmed the formation of a calix[8]arene bearing eight well-defined NHC palladium complexes. The macrocyclic structure of calix[8]arenes allowed for a scalable and chromatography-free catalyst synthesis under homogeneous conditions, while the catalytic reaction proceeded under heterogeneous conditions, just by changing the nature of the solvent. Indeed, when used as a suspension in ethanol, a high TON and TOF were obtained through a large panel of functionalized brominated substrates in C-C Suzuki-Miyaura couplings, with low metal contamination after simple filtration.

This chapter is dedicated to the main achievements since 2007 regarding the synthesis of BH3-phosphorus complexes. Among this class of compounds, phosphine-boranes are the most studied derivatives, mainly as valuable surrogates of phosphines, enabling easy handling and purification. In contrast, metal phosphido-boranes have so far only been considered as in situ intermediates in the P-functionalization of secondary phosphine-boranes. Thorough investigations of their structures as well as their chemical properties have recently been reported. Besides phosphine-boranes and their phosphides, new families of phosphorus-BH3 complexes, have emerged as useful precursors of new structures in the asymmetric series. New routes toward optically active phosphinous-acid boranes and their esters were developed and applied to the synthesis of enantiopure P-stereogenic secondary and tertiary phosphine-boranes. The stereoselective synthesis of P-stereogenic aminophosphine-boranes, precursors of a new class of chiral ligands, has been reported. Studies dealing with the synthesis and reactivity of phosphonite-boranes were successfully applied to the development of efficient syntheses of functionalized H-phosphinates, compounds difficult to access by other routes.

A versatile synthesis of 1,2,3-triazolyl-4-phosphines from the borane complexes of phosphino-alkynes is reported. The efficiency of the procedure relies on the use of readily available silyl-protected alkynylphosphine-boranes, which were subjected to desilylation with TBAF followed by copper-catalyzed azide-alkyne-cycloaddition in one pot. Subsequent treatment with DABCO afforded the targeted triazolylphosphines in high yields. The reported method was applied to the synthesis of the first example of an enantioenriched P-stereogenic triazolylphosphine (98.8% ee).

Copper-phosphido-borane complexes were synthesized and isolated for the first time. Their structures were experimentally and computationally investigated. They were shown to display catalytic activity in C(sp)-P bond formation., (This journal is © The Royal Society of Chemistry 2012)

The configurational stability of biaryl motifs is addressed for the 1-naphthyl-N-benzimidazolyl motif substituted by a single diphenylphosphinyl group at the 2-position. The atropoenantiomers of the N-methylated cation H-MIOP, a less sterically locked analogue of the neutral H-MOP ligand, were resolved by enantiospecific cleavage of the N(2)C-P bond of the resolved enantiomers of BIMIONAP. The latter were obtained by enantiospecific N-methylation of the previously resolved enantiomers of neutral BIMINAP. PdCl(2) complexes of the P,C-chelating N-heterocyclic carbene (NHC)-phosphine ligands derived from (R)- and (S)-H-MIOP were prepared by two enantiospecific routes: by N(2)C-P bond cleavage from the (R)- and (S)-BIMIONAP-PdCl(2) complexes, or by simultaneous coordination of the P and C atoms of the in situ generated free NHC-phosphine. The enantiomerization pathways of H-MOP, H-MIOP, and corresponding NHC-phosphine have been investigated at the B3PW91/6-31G(d,p) level of theory. The calculated enantiomerization barriers of H-MOP and H-MIOP in acetonitrile are equal to 176.0 and 146.4 kJ mol(-1), respectively, and are mainly determined by the distortion of the naphthalene and/or benzimidazole motifs in the transition state. Beyond the stability of their optical rotation at room temperature, the respective calculated Oki's racemization temperatures of 334 and 225 °C allowed us to consider both ligands as configurationally stable., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Whereas the external nucleophilic reactivity of α-amidiniophosphines has been previously illustrated by their complexation to transition-metal centers, their internal electrophilic reactivity is herein investigated by using BIMIONAP (BIMIONAP=N-methylated BIMINAP cation, BIMINAP=formal contraction of the acronyms BIMIP=2,2'-bis(diphenylphosphino)-1,1'-bibenzimidazole and BINAP=2,2'-bis(diphenylphosphino)-1,1'-binaphthyl). Reaction of tetraethylammonium chloride with free BIMIONAP is found to induce heterolytic cleavage of the N(2)C-P bond to give chlorodiphenylphosphine and a transient phosphine-N-heterocyclic carbene (NHC) species that is trapped in situ by protonation to the corresponding phosphine-benzimidazolium cation. When the chloride anion reacts with the cationic [Pd(η(2)-BIMIONAP)Cl(2)] complex, the same cleavage occurs and the phosphine-NHC moiety is trapped in the corresponding [PdCl(2)(η(2)-phosphine-NHC)] complex. When the chloride anion reacts with the dicationic [Pd(π-allyl)(η(2)-BIMIONAP)](+) complex, allyldiphenylphosphine is produced, and the [PdCl(η(2)-phosphine-NHC)(PPh(2)CH(2)CH=CH(2))](+) complex is obtained. Reaction of free BIMIONAP with the harder n-butyllithium nucleophile also induces heterolytic cleavage of the N(2)C-P bond, from which the phosphine-NHC moiety is trapped by hydrolysis of the benzimidazole ring or by P,C-sulfurization. Cleavage of a C-P bond with the weak Cl(-) nucleophile to release the reactive NHC moiety (according to the unusual scheme C-P+Cl(-)→C:+Cl-P) is a definite experimental indication of the dative nature of the N(2)C-P bond of amidiniophosphines, which are, therefore, better described as NHC→phosphenium adducts. This interpretation is supported by the calculation, at the DFT level, of a heterolytic dissociation mode of the N(2)C-P bond lower in energy than the homolytic one. A mesomeric description of the NHC→phosphenium entity is also proposed on the basis of electron localization function (ELF) and atoms in molecules (AIM) analyses. Finally ELF and AIM-based Fukui indices, molecular orbitals, and MESP analyses show that the initial attack of Cl(-) takes place at the carbenic atom of BIMIONAP.

Enantiomeric resolution of the rac-biminap ligand is achieved through fractional crystallization of four diastereoisomeric palladium complexes involving ortho-metallated enantiomerically pure (R)-dimethyl(1-naphthylethyl)amine as a chiral auxiliary. After decomplexation, the absolute configuration of (R)-biminap and (S)-biminap has been unambiguously attributed by single-crystal X-ray crystallography, and their stereochemical purity is confirmed by measurement of their optical rotation and by re-derivatization with the initial resolving chiral complex. Palladium complexes of biminap are shown to efficiently catalyze Tsuji-Trost allylic substitution of 3-acetoxy-1,3-diphenylpropene by sodium dimethyl malonate. In the asymmetric version using the enantiomerically pure (R)-biminap ligand, significant solvent and anion effects are evident, and an ee up to 90% is obtained.

Atropochiral NHC-phosphonium ylides based on the naphthyl-benzimidazolyl core are targeted as strongly sigma-donor C,C-chelating ligands of transition metals. The ligand core is shown to act in either a monodentate (through the carbene center) or bidentate (through the carbene and the ylide centers) fashion in seven palladium(ii) complexes obtained by two sequential strategies. In particular, the enantiomerically pure ortho-palladated (S)-dimethyl(1-phenylethyl)amine co-ligand is used as the chiral resolving agent for the separation of diastereoisomeric NHC-ylide complexes by fractional crystallization. Hydrochloric treatment of either diastereoisomer was found to keep intact the two carbon-palladium bonds, while affording the corresponding enantiomeric beta-zwitterionic NHC-ylide palladate complexes. The absolute configuration of the chirally isolated C,C-chelating ligand was finally confirmed by X-ray crystallography.