Microwave-Enhanced Asymmetric Transfer Hydrogenation of<i>N</i>-(<i>tert</i>-Butylsulfinyl)imines
作者:Óscar Pablo、David Guijarro、Miguel Yus
DOI:10.1002/ejoc.201402884
日期:2014.11
This work was generously supported by the Spanish Ministerio de Ciencia e Innovacion (MICINN) (grant numbers CONSOLIDER INGENIO 2010, CSD2007-00006, CTQ2007-65218 and CTQ2011-24151) and the Generalitat Valenciana (PROMETEO/2009/039 and FEDER). O. P. thanks the Spanish Ministerio de Educacion for a predoctoral fellowship (grant number AP-2008-00989).
A highly enantioselective intermolecular benzylic C(sp3)−H bond amination by using a chiral cationic copper catalyst and oxidant di-tert-butyl peroxide is reported. This mild, straightforward method can be used to transform an array of feedstock alkylarenes and amides into chiral amines with high enantioselectivities, and it has good functional group tolerance and a broad substrate scope.
Commercially available transaminases are valuable tools for the synthesis of chiral amine building blocks and are very accessible to the synthetic chemistry community. We demonstrate that selected commercially available enzymes from Codexis’ transaminase collection can accept and aminate bulky-bulky ketones in up to 99 % ee.
Kinetic Resolution of Amines via Dual Catalysis: Remarkable Dependence of Selectivity on the Achiral Cocatalyst
作者:Nisha Mittal、Diana X. Sun、Daniel Seidel
DOI:10.1021/ol301155b
日期:2012.6.15
A dual-catalysis/anion-binding approach with a chiral hydrogen bonding (HB) catalyst and an achiral nucleophilic cocatalyst was applied to the kinetic resolution of amines. Out of a structurally diverse collection of 22 nucleophilic species, 4-di-n-propylaminopyridine emerged as the most efficient cocatalyst, allowing for the kinetic resolution of benzylic amines with s-factors of up to 67.
One-Pot Synthesis of Chiral Nonracemic Amines
作者:Caroline Roe、Heather Hobbs、Robert A. Stockman
DOI:10.1021/jo201849j
日期:2011.11.18
One-pot five-component reactions of oxathiazolidine-S-oxides with mesitylmagnesiumbromide, lithium bis(trimethylsilyl)amide, aldehydes and Grignard reagents afford chiral nonracemic amines or sulfinamides in good yields and high stereoselectivities.