Asymmetric synthesis of chiral amines by highly diastereoselective 1,2-additions of organometallic reagents to N-tert-butanesulfinyl imines
作者:Derek A. Cogan、Guangcheng Liu、Jonathan Ellman
DOI:10.1016/s0040-4020(99)00451-2
日期:1999.7
High yielding and highly diastereoselective methods for 1,2-additions of organometallic reagents to N-tert-butanesulfinyl aldimines (2) and N-tert-butanesulfinyl ketimines (3) are described. The additions of alkyl, aryl, alkenyl, and allyl carbanions to a diverse set of imines with different steric and electronic properties are demonstrated. Acidic methanolysis of the sulfinamide products (4 and 6)
Chiral quaternary benzophenone hydrazonium salt derivatives; Efficient chiral catalysts for the enantioselective phase-transfer alkylation of imines. Application to synthesis of chiral primary amines
作者:J.Jamal Eddine、M. Cherqaoui
DOI:10.1016/0957-4166(95)00149-j
日期:1995.6
(2S)-1-Methyl-1-[N-(diphenylmethylene)]-2-hydroxymethylpyrrolidine hydrazonium iodide I-a has been designed to catalyse the enantioselective phase-transfer alkylation of N-(diphenylmethylene) benzenemethanamine II. Although the weak acidic character of the latter, alkylations have been performed within reasonable reaction times. Optically active Primary amines III a-e have been prepared in good chemical yields and up to 94% e.e. using 2-5 mol-% of the chiral catalyst only.
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.