Intermolecular Alkyl Radical Additions to Enantiopure N-tert-Butanesulfinyl Aldimines
摘要:
The sulfinyl group In (R)-N-tert-butanesulfinyl aldimines provides efficient control of the stereoselectivity in the intermolecular reactions with alkyl radicals. The methodology is applicable to aryl, heteroaryl, benzyl, and alkynyl imines, even those containing CN, CO2Me, COR, and OH groups. The best results are attained with hindered radicals (tertiary and secondary ones) without C=N bond reduction. This reaction complements the well-established organometallic additions to N-sulfinyl aldimines to obtain enantiomerically pure functionalized a-branched primary amines.
Synthesis of highly enantiomerically enriched amines by the diastereoselective addition of triorganozincates to N-(tert-butanesulfinyl)imines
作者:Raquel Almansa、David Guijarro、Miguel Yus
DOI:10.1016/j.tetasy.2008.10.012
日期:2008.11
different from the ones observed with the corresponding Grignardreagents, which allows, in several cases, the preparation of both enantiomers of an amine from the same imine substrate. When mixed triorganozincates are used, one can take advantage of the slow transfer rate of the methyl group to use it as a non-transferable one. Both aromatic and aliphatic aldimines, as well as activated ketimines, are good