Enantiocontrolled Synthesis of Trialkyl-Substituted Stereogenic Carbons. A General Route to <i>cis-</i>3,5-Dialkyl γ-Lactones
作者:David Díaz、Víctor S. Martín
DOI:10.1021/ol991287b
日期:2000.2.1
[GRAPHICS]Lewis acid treatment of tertiary Co-2(CO)(6)-propargylic alcohols having a stereochemically defined benzyloxy group at the gamma-benzyl position yielded after cobalt demetalation sec-dialkyl bishomopropargylic alcohols in good yields. The reaction is highly stereoselective and predictable, providing pure stereoisomers. The use of benzyl-alpha,alpha'-d(2) ethers permitted the stereoselective d-labeling of methines and methylenes, Very simple chemical manipulations provided a general methodology to obtain the enantiomers of 3,5-dialkyl-gamma-lactones.