Diastereoselective Synthesis of Cyclopropyl Boronic Esters
作者:Jörg Pietruszka、Markus Widenmeyer
DOI:10.1055/s-1997-5790
日期:1997.8
The conversion of simple 1-alkynes to optically active 2-alkyl-cyclopropan-1-ols is conveniently achieved by a simple protocol. The key step is the cyclopropanation of alkenyl boronic esters derived from (+)-diisopropyl L-tartrate and alkenyl boronic acids. It has been found that best yields could be obtained using diazomethane and palladium(II) acetate as catalyst. The systematic investigation of parameters influencing this reaction led to an improvement of the diastereoselectivity of the transformation.
Chromium(<scp>II</scp>)-mediated conversion of α,β-unsaturated aldehydes to cyclopropanols
作者:David Montgomery、Karen Reynolds、Paul Stevenson
DOI:10.1039/c39930000363
日期:——
Cromium(II) chloride converts α,β-unsaturated aldehydes to the corresponding Cyclopropanols.
氯化铬(II)可将δ、δ-不饱和醛转化为相应的环丙醇。
Diasteroselective Preparation of Cyclopropanols Using Methylene Bis(iodozinc)
作者:Kevin Cheng、Patrick J. Carroll、Patrick J. Walsh
DOI:10.1021/ol200597h
日期:2011.5.6
A diastereoselective synthesis of trans-2-substituted cyclopropanols is outlined. Bimetallic CH2(ZnI)(2) was found to react with alpha-chloroaldehydes to give cyclopropanols in yields of 64-89% and dr's >= 10:1. The high trans-selectivity resulted from equilibration of the cyclopropoxide intermediates.
Asymmetric cyclopropanation of 1-alkenylboronic esters and its application to the synthesis of optically active cyclopropanols
作者:Toshiro Imai、Hiroshi Mineta、Shinya Nishida
DOI:10.1021/jo00304a004
日期:1990.8
IMAI, TOSHIRO;MINETA, HIROSHI;NISHIDA, SHINYA, J. ORG. CHEM., 55,(1990) N7, C. 4986-4988