The Journal of Organic Chemistry

Vinylic organoboranes. 7. Stereoselective synthesis of (E)-(1-substituted-1-alkenyl) boronic esters by the nucleophilic substitution of (Z)-(1-bromo-1-alkenyl) boronic …

HC Brown, T Imai, NG Bhat

Index: Brown, Herbert C.; Imai, Toshiro; Bhat, N. G. Journal of Organic Chemistry, 1986 , vol. 51, # 26 p. 5277 - 5282

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Citation Number: 3

Abstract

The title compounds,(E)-R1CH== CR2B (OR) 2 (4a-g), are prepared in a highly regio-and stereoselective manner by the reaction of (Z)-R'CH= CBrB (OR) 2 (3a-g) with R2Li or R2MgX. The stereochemistry was established in two cases by isolating the E isomers 4 (R', R2= n-Bu; R'= i-Pr, R2= Me) in pure form and comparing the products with the corresponding 2 isomers prepared by hydroboration of appropriate internal alkynes. ...