Electronic and steric effects of ligands as control elements for rhodium-catalyzed asymmetric hydroformylation. Part 3: Highly active hydroformylation of styrene
作者:Csaba Hegedüs、József Madarász、Ildikó Gergely、Áron Szöllo˝sy、Axel Monsees、Thomas Riermeier、József Bakos
DOI:10.1016/j.tetasy.2004.07.015
日期:2004.8
The electronic and steric effects in the rhodium diphosphinite catalyzed asymmetric hydroformylation were investigated. Phosphinite basicity was varied by using 4-CH3, 4-CF3, 3,5-(CH3)(2) and 3,5-(CF3)(2) substituents on the diphenylphosphine moieties. Two series of ligands based on (S)-BINOL and (S)-H-8-BINOL were synthesized. In the hydroformylation of styrene an increase in l:b ratio, in activity and in enantioselectivity was observed with decreasing phosphinite basicity. (C) 2004 Elsevier Ltd. All rights reserved.