61594 20200221144249.0 doi 10.1016/j.tetasy.2016.04.006 sideral 94931 ART-2016-94931 eng (orcid)0000-0003-4196-5856 Carmona, Daniel Asymmetric 1, 3-dipolar cycloaddition reactions between methacrylonitrile and nitrones catalysed by well-defined M(diphosphane) (M=Rh, Ir) complexes 2016 Access copy available to the general public Unrestricted The cationic half-sandwich aqua-complexes (¿ 5-C5Me5)M(PP*)(H2O)]SbF6]2 M=Rh, Ir; PP* =(R)-Benphos, (R)-Cyphos, (2R, 4R)-Norphos] catalyse the 1, 3-dipolar cycloaddition reaction of nitrones with methacrylonitrile with perfect regioselectivity, low-to-perfect endo-selectivity and low-to-moderate enantioselectivity. The active species involved in the catalytic process, (¿ 5-C5Me5)M(PP*)(methacrylonitrile)]SbF6]2, have been isolated and characterised as mixtures of the (S)- and (R)-at-metal epimers. NMR measurements of these mixtures indicated that the (R M)-isomers epimerise to the corresponding (S M) counterparts. The molecular structure of the rhodium complex (S Rh, R C)-(¿ 5-C5Me5)Rh((R)-Benphos)(methacrylonitrile)]SbF6]2 has been determined by X-ray diffraction methods. Diastereomerically pure (S Rh, R C)-(¿ 5-C5Me5)Rh(PP*)(methacrylonitrile)]SbF6]2 compounds catalyse stoichiometrically the above mentioned dipolar cycloaddition reaction with up to 90% enantiomeric excess, thus indicating the influence of the metal handedness on the catalytic stereochemical outcome. Catalysts can be recycled up to three times without a significant loss of either activity or selectivity. info:eu-repo/grantAgreement/ES/DGA/E63 info:eu-repo/grantAgreement/ES/MINECO/Consolider-Ingenio/CSD2006-0015 info:eu-repo/grantAgreement/ES/MINECO/CTQ2012-32095 info:eu-repo/grantAgreement/ES/MINECO/CTQ2015-66079-P info:eu-repo/semantics/openAccess by-nc-nd http://creativecommons.org/licenses/by-nc-nd/3.0/es/ 2.126 2016 CHEMISTRY, INORGANIC & NUCLEAR 18 / 46 = 0.391 2016 Q2 T2 CHEMISTRY, ORGANIC 29 / 59 = 0.492 2016 Q2 T2 CHEMISTRY, PHYSICAL 80 / 145 = 0.552 2016 Q3 T2 0.754 2016 Inorganic Chemistry 2016 Q2 Physical and Theoretical Chemistry 2016 Q2 Organic Chemistry 2016 Q2 Catalysis 2016 Q3 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion (orcid)0000-0002-6160-3046 Viguri, Fernando Universidad de Zaragoza Asenjo, Ainara (orcid)0000-0001-9071-563X Lamata, Pilar Universidad de Zaragoza (orcid)0000-0001-8054-2237 Lahoz, Fernando J. Universidad de Zaragoza (orcid)0000-0002-7063-1292 García-Orduña, Pilar Universidad de Zaragoza 2010 760 Universidad de Zaragoza Dpto. Química Inorgánica Área Química Inorgánica 27, 11-12 (2016), [26 pp.] Tetrahedron: asymmetry Tetrahedron: Asymmetry 0957-4166 637869 http://zaguan.unizar.es/record/61594/files/texto_completo.pdf Postprint 78521 http://zaguan.unizar.es/record/61594/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:61594 articulos driver 2020-02-21-13:26:54 ARTICLE