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The control of surface wettability with polyphenol coatings has been at the forefront of materials research since the late 1990s, when robust underwater adhesion was linked to the presence of L-DOPA-a catecholic amino acid-in unusually high amounts, in the sequences of several mussel foot proteins. Since then, several successful approaches have been reported, although a common undesired feature of most of them is the presence of a remnant color and/or the intrinsic difficulty in fine-tuning and controlling the hydrophobic character. We report here a new family of functional catechol-based coatings, grounded in the oxidative condensation of readily available pyrocatechol and thiol-capped functional moieties. The presence of at least two additional thiol groups in their structure allows for polymerization through the formation of disulfide bonds. The synthetic flexibility, together with its modular character, allowed us to: (I) develop coatings with applications exemplified by textiles for oil-spill water treatment; (II) develop multifunctional coatings, and (III) fine-tune the WCA for flat and textile surfaces. All of this was achieved with the application of colorless coatings.

Compuesto derivado de catecol de fórmula (I): **(Ver fórmula)** en la que, X1 se selecciona del grupo que consiste en hidrógeno y un sustituyente -SR2, X2 y X3 son átomos de hidrógeno, R1 y R2 se seleccionan independientemente del grupo que consiste en: - un resto FUNC, el cual se selecciona del grupo que consiste en: - un resto alquilo de fórmula -CnH2n+1, en la que n varía entre 12 y 18; - un resto alquenilo de fórmula -CnH2n-1, en la que n varía entre 2 y 6; - un resto alquinilo de fórmula -CnH2n-3, en la que n varía entre 2 y 6; - un resto polifluoroalquilo de fórmula -(CH2)p1-CnF2n+1, en la que p1 está comprendido entre 0 y 3, y n está 15 comprendido entre 5 y 8; - un resto de fórmula -(CHRCH2O)qR´, en la que R es un átomo de hidrógeno o un grupo metilo, y R' se selecciona entre un átomo de hidrógeno, un grupo alquilo C1-C10, alquenilo terminal C1-C18, alquinilo terminal C1-C18, -COOH, -NH2, -N3 o N-maleimido, y q es un valor comprendido entre 5 y 300; - una etiqueta fluorescente seleccionada entre compuestos fluorescentes con grupos tiol, fluoresceína, eosina, 20 rodaminas, derivados fluorescentes de boro-dipirrometeno (BODIPY); derivados fluorescentes de estructura azo (diazoarenos), derivados fluorescentes de piridino-metoxifenilenoxazoles (PyMPO), derivados fluorescentes de Lucifer Yellow, derivados fluorescentes de benzoxadiazol (BD), Fluorescent Red, Fluorescent Orange, y otros marcadores fluorescentes disponibles bajo marcas registradas (Atto y Alexa), que se pueden conjugar a través de grupos reactivos ad hoc; - un oligopéptido seleccionado entre glutationa y un oligopéptido compuesto de 5-25 aminoácidos, de los cuales del 20% al 100% son arginina; y - un resto -R3-S-Z, en el que, - S es un átomo de azufre, - R3 se selecciona del grupo que consiste en: - un resto alcandiilo de fórmula -(Cn´H2n´)-, en la que n´ está comprendido entre 2 y 18; - un resto (polialquilenoxi)alquilo de fórmula -(CHR''CH2O)q1(CHR''CH2)-, en la que R'' se selecciona del grupo qu

The hydrothiolation of activated alkynes is presented as an attractive and powerful way to functionalize thiols bearing catechols. The reaction was promoted by a heterogeneous catalyst composed of copper nanoparticles supported on TiO2 (CuNPs/TiO2) in 1,2-dichloroethane (1,2-DCE) under heating at 80 °C. The catalyst could be recovered and reused in three consecutive cycles, showing a slight decrease in its catalytic activity. Thiol derivatives bearing catechol moieties, obtained through a versatile Michael addition, were reacted with different activated alkynes, such as methyl propiolate, propiolic acid, propiolamide or 2-ethynylpyridine. The reaction was shown to be regio- and stereoselective towards anti-Markovnikov Z-vinyl sulfide in most cases studied. Finally, some catechol derivatives obtained were tested as ligands in the preparation of coordination polymer nanoparticles (CNPs), by taking the advantage of their different coordination sites with metals such as iron and cobalt.

The present invention relates to catechol-derivative compounds of formula (I), as well as polymeric compounds obtained by condensation. The present invention also relates to the use of the compounds for preparing functional coatings and as adhesive substances

The adhesion of some marine organisms to almost any kind of surface in wet conditions has aroused increasing interest in recent decades. Numerous fundamental studies have been performed to understand the scientific basis of this behaviour, with catechols having been found to play a key role. Several novel bio‐inspired adhesives and coatings with value‐added performances have been developed by taking advantage of the knowledge gained from these studies. To date there has been no detailed overview focusing exclusively on the complex mode of action of these materials. The aim of this Review is to present recent investigations that elucidate the origin of the strong and versatile adsorption capacities of the catechol moiety and the effects of extrinsic factors that play important roles in the overall adhesion process, such as pH value, solvent, and the presence of metal ions. The aim is to detail the chemistry behind the astonishing properties of natural and synthetic catechol‐based adhesive materials.

The present invention relates to catechol-derivative compounds of formula (I), as well as polymeric compounds obtained by condensation. The present invention also relates to the use of the compounds for preparing functional coatings and as adhesive substances

The combination of the surface‐adhesive properties of catechol rings and functional moieties conveying specific properties is very appealing to materials chemistry, but the preparation of catechol derivatives often requires elaborate synthetic routes to circumvent the intrinsic reactivity of the catechol ring. In this work, functional catechols are synthesized straightforwardly by using the bioinspired reaction of several functional thiols with o‐benzoquinone. With one exception, the conjugated addition of the thiol takes place regioselectively at the 3‐position of the quinone, and is rationalized by DFT calculations. Overall, this synthetic methodology provides a general and straightforward access to functional and chain‐extended catechol derivatives, which are later tested with regard to their hydro‐/oleophobicity, colloidal stability, fluorescence, and metal‐coordinating capabilities in proof‐of‐concept applications.

A multicomponent 1,3-dipolar cycloaddition between heterocyclic aldehydes, amino esters and dipolarophiles is efficiently promoted by silver acetate as catalyst, and depending on the nature of the heterocycle and its reactivity the reaction requires 70 °C or rt to complete. Selected pharmacophores anchored to a formyl group are chromone, 5-methoxyindole, pyridoxal surrogates and a very attractive uracyl derivative. The preference of each tested amino esters towards different dipolarophiles is discussed. At the end, a selective reduction of the ester group allows to obtain a very interesting dideoxiazanucleoside derivative.

The asymmetric 1,3-dipolar cycloaddition of an imino ester 5 with tert-butyl acrylate is catalyzed by a dual chiral silver(I) complex formed from a chiral phosphoramidite 14 and the chiral silver(I) binolphosphate (R)-17. This reaction is selected to achieve the synthesis of enantiomerically enriched key structures to access the third generation of GSK HCV inhibitors. The scope of this dual chiral catalytic system is analyzed by employing different imino esters and dipolarophiles, and also compared with the same cycloaddition reactions performed with the chiral phosphoramidite 14·AgClO4 complex.

The asymmetric 1,3-dipolar cycloaddition of an imino ester 5 with tert-butyl acrylate is catalyzed by a dual chiral silver(I) complex formed from a chiral phosphoramidite 14 and the chiral silver(I) binolphosphate (R)-17. This reaction is selected to achieve the synthesis of enantiomerically enriched key structures to access the third generation of GSK HCV inhibitors. The scope of this dual chiral catalytic system is analyzed by employing different imino esters and dipolarophiles, and also compared with the same cycloaddition reactions performed with the chiral phosphoramidite 14·AgClO complex.

En la presente memoria se describe la síntesis de derivados de pirrolidina, pirrolizidina e indolizidina mediante diferentes metodologías que involicruan una cicloadición 1,3-dipolar multicomponente a través de iluros de azometino generados in situ, así como el estudio cinético de esta reacción vía dos componentes. En el Capítulo I, se describen diferentes métodos de estudio cinético para la interpretación y obtención de parámetros mecanísticos de dicha reacción a partir de la información obtenida mediante Análisis Térmico y más concretamente calorimetría diferencial de barrido. En el Capítulo II, dividido en tres partes, se describe la síntesis de pirrolidinas mediante cicloadición 1,3-dipolar multicomponente (a partir de iluros de azometino) térmica y por irradiación por microondas (Parte 1), catalizada por plata(I) (Parte II) y asimétrica mediante catálisis por plata(I) y un ligando quiral (Parte III); así como la posible aplicabilidad en la síntesis de productos naturales o que presenten actividad biológica. En el Capítulo III, se describe la síntesis de pirrolizidinas mediante la cicloadición 1,3-dipolar multicomponente con iluros de azometino con y sin uso de sales de plata(I), así como un ejemplo en la construcción de un esqueleto de indolizidina siguiendo la misma metodología. Finalmente se incluyen las conclusiones junto con otro tipo de anexos como son las referencias, abreviaciones y la biografía.

The synthesis of unnatural pyrrolizidines has been studied using a multicomponent-domino process involving proline or 4-hydroxyproline esters, an aldehyde and a dipolarophile. The formation of the iminium salt promotes the 1,3-dipolar cycloaddition affording highly substituted pyrrolizidines under mild conditions and high regio- and diastereoselectivities.

Binap-AgSbF6 catalyzed 1,3-dipolar cycloadditions between azomethine ylides and electrophilic alkenes are described and compared with analogous transformations mediated by other Binap-silver(I) salt complexes. Maleimides and 1,2-bis(phenylsulfonyl)ethylene are suitable dipolarophiles for obtaining very good enantioselectivities, even better values are generated by a multicomponent version. There are some very interesting applications of the disulfonylated cycloadducts in the total synthesis of cis-2,5-disubstituted pyrrolidines, precursors of natural products, or valuable intermediates in the synthesis of antiviral compounds.