{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,6]],"date-time":"2025-12-06T21:46:27Z","timestamp":1765057587380,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2016,9,6]],"date-time":"2016-09-06T00:00:00Z","timestamp":1473120000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The stereoselective reduction of imines with trichlorosilane catalyzed by chiral Lewis bases is a well-established procedure for the synthesis of enantio-enriched amines. Five supported cinchona-based picolinamides have been prepared and their activity tested in a model reaction. The comparison of different supporting materials revealed that polystyrene gave better results than silica in terms of stereoselectivity. The applicability of the solid-supported catalyst of choice to the reduction of different imines was also demonstrated. Additionally, for the first time, a catalytic reactor containing a polymer-immobilized chiral picolinamide has been employed for the stereoselective reduction of imines with trichlorosilane under continuous flow conditions.<\/jats:p>","DOI":"10.3390\/molecules21091182","type":"journal-article","created":{"date-parts":[[2016,9,6]],"date-time":"2016-09-06T10:10:16Z","timestamp":1473156616000},"page":"1182","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Stereoselective Reduction of Imines with Trichlorosilane Using Solid-Supported Chiral Picolinamides"],"prefix":"10.3390","volume":"21","author":[{"given":"S\u00edlvia","family":"Fernandes","sequence":"first","affiliation":[{"name":"Department of Chemistry and Chemistry Center of \u00c9vora, School of Science and Technology and Institute for Research and Advanced Studies, University of \u00c9vora, Rua Rom\u00e3o Ramalho 59, \u00c9vora 7000, Portugal"}]},{"given":"Riccardo","family":"Porta","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica, Universit\u00e0 degli Studi di Milano, Via Golgi 19, Milano 20133, Italy"}]},{"given":"Pedro","family":"Barrulas","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemistry Center of \u00c9vora, School of Science and Technology and Institute for Research and Advanced Studies, University of \u00c9vora, Rua Rom\u00e3o Ramalho 59, \u00c9vora 7000, Portugal"}]},{"given":"Alessandra","family":"Puglisi","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica, Universit\u00e0 degli Studi di Milano, Via Golgi 19, Milano 20133, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8248-1116","authenticated-orcid":false,"given":"Anthony","family":"Burke","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemistry Center of \u00c9vora, School of Science and Technology and Institute for Research and Advanced Studies, University of \u00c9vora, Rua Rom\u00e3o Ramalho 59, \u00c9vora 7000, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9568-9642","authenticated-orcid":false,"given":"Maurizio","family":"Benaglia","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica, Universit\u00e0 degli Studi di Milano, Via Golgi 19, Milano 20133, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2016,9,6]]},"reference":[{"key":"ref_1","unstructured":"Jacobsen, E.N., Pfaltz, A., and Yamamoto, H. 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Catal."},{"key":"ref_21","unstructured":"Attempts to monitor the reaction from 3 to C via solid state NMR were unsuccessful; a complete conversion of the primary amine into the corresponding picolinamide could not be confirmed."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"624","DOI":"10.1016\/j.reactfunctpolym.2013.01.009","article-title":"Reversible crosslinking of polymers bearing pendant or terminal thiol groups prepared by nitroxide-mediated radical polymerization","volume":"73","author":"Braslau","year":"2013","journal-title":"React. Funct. Polym."},{"key":"ref_23","unstructured":"The reaction in the presence of polystyrene supported primary amine 4 as catalyst gave amine 7a in 45% yield as a racemic mixture."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Barrulas, P.C., Genoni, A., Benaglia, M., and Burke, A.J. (2014). Cinchona-Derived Picolinamides: Effective Organocatalysts for Stereoselective Imine Hydrosilylation. Eur. J. Org. Chem., 7339.","DOI":"10.1002\/ejoc.201403180"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1699","DOI":"10.1016\/0957-4166(95)00215-B","article-title":"Preparation of 9-amino-(9-deoxy) cinchona alkaloids","volume":"6","author":"Brunner","year":"1995","journal-title":"Tetrahedron Asymmetry"}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/21\/9\/1182\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:30:14Z","timestamp":1760211014000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/21\/9\/1182"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,9,6]]},"references-count":25,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2016,9]]}},"alternative-id":["molecules21091182"],"URL":"https:\/\/doi.org\/10.3390\/molecules21091182","relation":{},"ISSN":["1420-3049"],"issn-type":[{"type":"electronic","value":"1420-3049"}],"subject":[],"published":{"date-parts":[[2016,9,6]]}}}