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The dual activation of simple substrates by the combination of organocatalysis and palladium catalysis has been successfully applied in a variety of different asymmetric transformations. Thus, the asymmetric α-allylation of carbonyl compounds, α-fluorination of acyl derivatives, decarboxylative protonation of β-dicarbonyl compounds, cyclization reactions of alkynyl carbonyl compounds and β-functionalization of aldehydes have been efficiently achieved employing this double-catalytic methodology ; MAFI thanks financial support from the Ministerio de Economía y Competitividad MINECO, CTQ 2012-35790) and the Consejería de Educación de la Comunidad de Madrid (AVANCAT, S2009/PPQ-1634). BM thanks the European Commission for a Marie Curie Integration Grant (FP7-PEOPLE-2012-CIG). IMP thanks financial support from the Ministerio de Ciencia e Innovación (MICINN) of Spain (CTQ2011-24165) and from the University of Alicante. DAA thanks financial support for the European Union (ORCA action CM0905) and from the University of Alicante

The dual activation of simple substrates by the combination of organocatalysis and palladium catalysis has been successfully applied in a variety of different asymmetric transformations. Thus, the asymmetric a-allylation of carbonyl compounds, a-fluorination of acyl derivatives, decarboxylative protonation of β-dicarbonyl compounds, cyclization reactions of alkynyl carbonyl compounds and β-functionalization of aldehydes have been efficiently achieved employing this double-catalytic methodology. ; MAFI thanks financial support from the Ministerio de Economía y Competitividad (MINECO, CTQ 2012-35790) and the Consejería de Educación de la Comunidad de Madrid (programme AVANCAT, S2009/PPQ-1634). BM thanks the European Commission for a Marie Curie Integration Grant (FP7-PEOPLE-2012-CIG). IMP thanks financial support from the Ministerio de Ciencia e Innovación (MICINN) of Spain (CTQ2011-24165) and from the University of Alicante. DAA thanks financial support for the European Union (ORCA action CM0905) and from the University of Alicante.

"N-Heterocyclic Carbenes in Transition Metal Catalysis and Organocatalysis" features all catalytic reactions enabled by N-heterocyclic carbenes (NHCs), either directly as organocatalysts or as ligands for transition metal catalysts. An explosion in the use of NHCs has been reported in the literature during the past seven years making this comprehensive overview highly apropos. This book begins with an introductory overview of NHCs which could have been subtitled all you need to know about NHCs. The main body of the book is dedicated to applications of NHCs in catalysis. In addition t

The synthesis of complex active molecules has afforded the search for new methods and new processes in organic synthesis. In this context, organic metal free catalysis has appeared as a powerful tool being complementary to metal catalysis in the field of asymmetric synthesis. The success of this methodology has been increasing in the last decade and the research for new organocatalytic systems as well as new applications has attracted the interest of many research groups. Among all organocatalysts, diarylprolinol derivatives have emerged as powerful scaffolds for asymmetric catalysis, proof of that is the huge number of publications reported using this kind of structure as catalysts. However, only in a few cases, different aspects of the catalysts structures and additional additives have been largely studied and a plausible explanation has been given. In this sense, this review treats to illustrate these important and scarce examples and to give a very general vision relating to the application of diarylprolinol derivatives in organocatalytic transformations from another point of view: structural aspects. The influence of catalyst structure, electronic effects, and the use of additives will be the aim of discussion and comment in this work. ; Financial support was provided by the Alexander von Humboldt Foundation (postdoctoral fellowship to E. M.-L.), and the Aragón I+D Foundation for a permanent contract, Ministry of Science and Innovation (MICINN, Madrid, Spain. Project CTQ2009-09028) and the Government of Aragón (Zaragoza, Spain, Project PI064/09) (R. P. H.). ; Peer Reviewed

[EN] The first enantioselective formal [3 + 2] cycloaddition between ¿-isocyanoesters and trifluoromethylketones to give 5-trifluoromethyl-2-oxazolines bearing two contiguous stereogenic centers, one of them being a quaternary stereocenter substituted with a CF3 group, has been developed. The reaction is based upon a multicatalytic approach that combines a bifunctional Brønsted base-squaramide organocatalyst and Ag+ as Lewis acid. The reaction could be achieved with a range of aryl and heteroaryl trifluoromethyl ketones, and the resulting oxazolines were obtained with good to excellent diastereo- and enantioselectivity. ; Financial support from the MINECO and FEDER (CTQ2017-84900-P). Access to NMR and MS facilities from SCSIE-UV. C.V. thanks the Spanish Government for a Ramon y Cajal contract (RyC-2016-20187). A.S.-M. thanks the Generalitat Valenciana and Fondo Social Europeo for a postdoctoral grant (APOST/2016/139). ; Martinez-Pardo, P.; Blay, G.; Vila, C.; Sanz-Marco, A.; Muñoz Roca, MDC.; Pedro, JR. (2019). Enantioselective Synthesis of 5-Trifluoromethyl-2-oxazolines under Dual Silver/Organocatalysis. The Journal of Organic Chemistry. 84(1):314-325. https://doi.org/10.1021/acs.joc.8b02808 ; S ; 314 ; 325 ; 84 ; 1

A highly enantioselective organocatalytic vinylogous Mukaiyama aldol reaction of silyloxy dienes and isatins under bifunctional organocatalysis is presented. Substituted 3-hydroxy-2-oxindoles are synthesised in good yields and enantioselectivities. These synthetic intermediates are used for the construction of more complex molecules with biological properties such as the formal synthesis of a CB2 agonist presented ; The Spanish Government (CTQ2015-64561-R) is acknowledged. V. L.-M. thanks the Autonomous university of Madrid for a predoctoral fellowship (FPI-UAM). J. A. F.-S. thanks the Spanish Government for a Juan de la Cierva Contract

A straightforward and robust modular synthetic approach was developed for the asymmetric synthesis of imidazolium salts, in which several engineered molecular vectors were considered to evaluate their toxicological profile. The diastereoselective synthesis of cis-3-(1H-imidazol-1-yl)cyclohexanol was achieved by the Michael addition of imidazole to cyclohex-2-en-1-one under microwave conditions followed by reduction of the ketone. The racemic cis-alcohol obtained was successfully resolved through a lipase-catalysed kinetic resolution, Pseudomonas cepacia lipase proved to be a good biocatalyst for the exclusive acetylation of the (1R,3S)-cis enantiomer. Using the remaining (1S,3R)-cis alcohol enantiomer as a synthetic precursor, the optically active (1R,3R)-trans alcohol enantiomer was also prepared. The corresponding chiral salts and ionic liquids were obtained via quaternisation with alkyl halides, followed by anion exchange with inorganic salts. In this manner, a family of novel imidazolium-based ionic liquids was prepared, and their properties as phase-transfer catalysts in the Michael addition of diethyl malonate to trans-chalcone were analysed. The toxicity of these compounds against E. coli cells was also evaluated to understand their structural implications through the presented systematic synthetic approach. ; This project was supported by the BIOTRAINS Marie Curie Initial Training Network, financed by the European Union through the 7th Framework People Programme (grant agreement number 238531). Financial support from the Spanish MICINN (Projects CTQ-2007-61126, MAT-2006-01997 and MAT-2010-15094) is also gratefully acknowledged. V. G. -F. and I. L. acknowledge MICINN for their research contracts under the Ramo´n y Cajal Program

Halogen bonding represents a powerful tool in the field of noncovalent interactions. However, applications in enantioselective recognition and catalysis remain almost nonexistent, due in part to the distinct features of halogen bonds, including long covalent and noncovalent bond distances and high directionality. Herein, this work presents a novel chiral tetrakis-iodo-triazole structure as a neutral halogen bond donor for both chiral anion-recognition and enantioinduction in ion-pair organocatalysis. NMR-titration studies revealed significant differences in anion affinity between the halogen bonding receptor and its hydrogen bonding parent. Selective recognition of chiral dicarboxylates and asymmetric induction in a benchmark organocatalytic reaction were demonstrated using the halogen bond donor. Inversions in the absolute sense of chiral recognition, enantioselectivity, and chiroptical properties relative to the related hydrogen donor were observed. Computational modeling suggested that these effects were the result of distinct anion-binding modes for the halogen- versus hydrogen-bond donors. ; This publication is part of a project that has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 847413. Scientific work published as part of an international co-financed project founded from the programme of the Minister of Science and Higher Education entitled "PMW" in the years 2020 - 2024; agreement no. 5005/H2020-MSCA-COFUND/2019/2"

This computational and experimental study represents a case where "push–pull π+/π–" (PPππ) systems have shown a concrete application in chemistry apart from spectral tuning. The most notable finding of this investigation was that a mode of interaction unprecedented in catalysis, a PPππ system, played a crucial role in the Henry reaction catalyzed by a NOBIN-based squaramide. The results show that the PPππ system stabilizes the most favorable pathway, P1, with 2.7–4.7 kcal/mol. This is vital for the differentiation in energy of P1 over the remaining pathways and directly affects both the reactivity and stereoselectivity of this reaction. These results suggest that PPππ systems are promising tools with great potential for catalysis. ; We thank the Government of Aragon DGA (Research Group E-104) for financial support of our research. J.V.A.-R. thanks the DGA for a predoctoral contract. ; Peer reviewed

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Catalysis, copyright ©2018 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/abs/10.1021/acscatal.8b01331 ; A bifunctional photoaminocatalyst based on imidazolidinone and thioxanthone is presented. The preparation of these catalysts proceeds in a two-step synthesis that allows an easy tuning of the steric properties. The photophysical and electrochemical data of the imidazolidinone photocatalysts have been determined, indicating that the catalysts can work under visible light conditions. To corroborate the experimental observations, ground state geometry optimization and energy transition studies of thioxanthone and bifunctional catalyst 4c were optimized by time-dependent density functional theory (TD DFT) calculations. The alkylation of aldehydes with this photoaminocatalyst works with high enantioselectivities and yields due to the stereoelectronic properties of the catalyst. A rational mechanistic cycle based on different mechanistic experiments, TD DFT calculations, and laser flash photolysis is presented ; The Spanish Government (CTQ2015-64561-R) and the European Research Council (ERC-CG, Contract 647550) are acknowledged

The 1,2-aminoindanol scaffold has been found to be very efficient, enhancing the enantioselectivity when present in organocatalysts. This may be explained by its ability to induce a bifunctional activation of the substrates involved in the reaction. Thus, it is easy to find hydrogen-bonding organocatalysts ((thio)ureas, squaramides, quinolinium thioamide, etc.) in the literature containing this favored structural core. They have been successfully employed in reactions such as Friedel-Crafts alkylation, Michael addition, Diels-Alder and aza-Henry reactions. However, the 1,2-aminoindanol core incorporated into proline derivatives has been scarcely explored. Herein, the most representative and illustrative examples are compiled and this review will be mainly focused on the cases where the aminoindanol moiety confers bifunctionality to the organocatalysts. ; We thank the "Ministerio de Economía y Competitividad" (MINECO, Project CTQ2013-44367-C2-1-P), the University of Zaragoza (JIUZ-2014-CIE-07), the High Council of Scientific Investigation (CSIC) (PIE-201580I010) and the Government of Aragon DGA (Research Group E-104) for financial support of our research. ; Peer Reviewed

Strategic move: Isatin as a core structure has inspired the development of useful catalytic strategies to give access to interesting molecular architectures with biological activity. ; We thank the Ministry of Science and Innovation (CTQ2010-19606-C02-01) and Aragon Government (E-10) for financial support of our research. R.H. and S.M. thank the Iranian Government for their fellowships and financial support. ; Peer Reviewed

We present here the results obtained in our study on organocatalytic enantioselective Michael addition reaction of acetone to different nitroolefines using (2R,3aS,7aS)-octahydroindole-2-carboxylic acid [(R,S,S)-Oic] as a new and suitable catalyst for this process. Computational calculations support the results obtained with (R,S,S)-Oic versus its diastereomeric form (S,S,S)-Oic. The final products are obtained in good yields and moderate enantioselectivities (up to 58% ee). © Georg Thieme Verlag Stuttgart. ; We thank the Spanish National Research Council (CSIC. Project PIE-200880I260), the Ministry of Science and Innovation (MICINN, Madrid; Projects CTQ2009-09028, CTQ2010-19606, and CTQ2010-17436) and the Government of Aragón (Zaragoza; Project PI064/09 and Research Groups E-10 and E-40) for financial support of our research. R.P.H. thanks the Aragón I + D Foundation for her permanent contract. ; Peer Reviewed

The monoguanylation of (1S,2S)- and (1R,2R)-cyclohexane-1,2-diamine affords chiral primary amine-guanidines that are used as chiral organocatalysts in the enantioselective Michael addition of aldehydes, particularly α,α-disubstituted aldehydes, to maleimides. The reaction is carried out in the presence of imidazole, as an additive, in aqueous N,N-dimethylformamide, as the solvent, and affords the corresponding enantioenriched succinimides in high or quantitative yields with enantioselectivities up to 96 % ee. Theoretical calculations (DFT and M06–2X) suggest a different hydrogen-bonding coordination pattern between the maleimide (C=O) and the catalyst (NH groups) is responsible for the enantioinduction switch that is observed when the reaction is carried out using primary amine-guanidines versus primary amine-thioureas as the organocatalysts. ; The authors thank the Spanish Ministerio de Economía y Competitividad (MEC) (projects CTQ2010-20387, CTQ2010-21263-C02, and Consolider Ingenio 2010, CSD2007-00006), the Fondos Europeos para el Desarrollo Regional (FEDER), the COST Action CM0905 "Organocatalysis", the Generalitat Valenciana (Prometeo/2009/039), the Basque Government (GV grant IT-291-07), the University of Alicante, and the University of the Basque Country for the financial support.

This Feature Article describes our mechanistic studies in organocatalytic Rauhut-Currier-type reactions and some applications in target-oriented synthesis. The developed approach involves the cyclization of two tethered Michael acceptors via dienamine intermediates and leads to highly functionalized cycloalkenes. The utility of these intermediates is further demonstrated by the synthesis of biologically important targets, such as optically active iridoid derivatives. 1 Introduction 2 Organocatalytic Cyclization of Tethered α,β-Unsaturated Carbonyl Compounds; Synthesis of Cyclopentene Derivatives 2.1 Mechanistic Proposal 2.1.1 ESI-HRMS Measurements 2.1.2 NMR Experiments 2.1.3 Complementary Reactivity 2.2 Synthetic Applications 3 Organocatalytic Cyclization of Tethered α,β-Unsaturated Carbonyl Compounds; Synthesis of Cyclohexene Derivatives 4 Conclusions. © Georg Thieme Verlag Stuttgart New York. ; We thank the Fonds der Chemischen Industrie for a Dozentenstipendium (M.C.), the DFG (Priority Program 1179 - Organocatalysis), Spanish Government (CTQ2010-19606-C02-01), the Humboldt Foundation (postdoctoral (E.M.-L.) and experienced researcher (R.P.H.) fellowships). ; Peer Reviewed