Iridium phosphite-oxazoline catalysts for the highly enantioselective hydrogenation of terminal alkenes
2009 (English)In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 131, no 34, 12344-12353 p.Article in journal (Refereed) Published
A modular library of readily available phosphite-oxazoline ligands (L1-L16a-f) has been successfully applied for the first time in the Ir-catalyzed asymmetric hydrogenation of a broad range of highly unfunctionalized 1,1,-disubstituted terminal alkenes. Enantioselectivities up to >99% and full conversions were obtained in several 1,1-disubstituted alkenes, including substrate classes that have never been asymmetrically hydrogenated before (i.e., 1,1-heteoraryl-alkyl, 1,1-diaryl, trifluoromethyl, etc.). The results indicated that these catalytic systems have high tolerance to the steric and electronic requirements of the substrate and also to the presence of a neighboring polar group. The asymmetric hydrogenations were also performed using propylene carbonate as solvent, which allowed the Ir catalyst to be reused and maintained the excellent enantioselectivities.
Place, publisher, year, edition, pages
2009. Vol. 131, no 34, 12344-12353 p.
IdentifiersURN: urn:nbn:se:uu:diva-121863DOI: 10.1021/ja904152rISI: 000269379600068PubMedID: 19658416OAI: oai:DiVA.org:uu-121863DiVA: diva2:306888