Application of 1,2:5,6-di-O-cyclohexylidene-d-mannitol as the chiral director in Matteson’s asymmetric homologation
摘要:
1,2:5,6-Di-O-cyclohexylidene-D-mannitol is the good chiral director in Matteson's asymmetric homologation as indicated by the high enantiomeric excesses (ee's) of the secondary alcohols produced by treatment of the homologation products with alkyllithium or Grignard reagents followed by oxidation. (C) 1999 Elsevier Science S.A. All rights reserved.
Indium-mediated Barbier-type allylation of aldehydes as a convenient method for the highly enantioselective synthesis of homoallylic alcohols
作者:Lacie C. Hirayama、Soya Gamsey、Daniel Knueppel、Derek Steiner、Kelly DeLaTorre、Bakthan Singaram
DOI:10.1016/j.tetlet.2005.01.169
日期:2005.3
enantioselective allylation of both aromatic and aliphatic aldehydes using commercially available (1S,2R)-(+)-2-amino-1,2-diphenylethanol as a chiral auxiliary. Using only two equivalents of allyl bromide, excellent yields and very good to excellent enantioselectivities are obtained. To our knowledge, the enantioselectivities reported herein are the highest obtained for indium-promoted allylations of carbonyl
Novel Lewis Acid-Assisted Chiral Lewis Acid (LLA) System: Development of Boroxin-Ti-BINOL-Catalyzed Asymmetric Allylation of Aldehydes
作者:Hisashi Yamamoto、Guoyao Xia、Kazutaka Shibatomi
DOI:10.1055/s-2004-832830
日期:——
The formation of hetero multimetallic complex having B-O-Ti bond could increase the Lewis acidity of titanium. A novel LLA system made up of Ti-BINOL and 4-(trifluoromethyl)phenyl-boroxin dramatically accelerated the allylation reaction of aldehyde with high enantioselectivity.
High-Pressure Enantioselective Allylation of Aldehydes Catalyzed by (Salen)Chromium(III) Complexes
作者:Janusz Jurczak、Piotr Kwiatkowski
DOI:10.1055/s-2004-836067
日期:——
The enantioselective addition of allyltributyltin to simple aldehydes (2a-1), catalyzed by chiral (salen)Cr(III) complexes 1, has been studied. The reaction proceeds smoothly with low loading (1-2 mol%) of (salen)Cr(III)BF 4 (la) and allyltributyltin under high-pressure conditions (10 kbar) in good yield and ee values in the range of 35-79%.
unit with a conformationally rigid chiral backbone has been designed and synthesized in an enantiomerically pure form to utilize in the Lewis base-catalyzed Sakurai–Hosomi–Denmark-type allylation reaction. The chiral pyridine N-oxide in 1:1 mixture of chloroform and 1,1,2,2-tetrachloroethane produced the homoallylic alcohols in up to 98% yield and up to 94% ee.
A practical and efficient method for enantioselective allylation of aldehydes
作者:E. J. Corey、Chan Mo Yu、Sung Soo Kim
DOI:10.1021/ja00196a082
日期:1989.7
La reaction d'(allyl-2 diphenyl-4,5 ditosyl-1,3)diazaborolidines-1,3,2 chirales avec des aldehydes fournit des alcools homoallyliques de maniere enantioselective
La 反应 d'(allyl-2 diphenyl-4,5 ditosyl-1,3)diazaborolidines-1,3,2 手性 avec des aldehydes Fournit des alcools homoallyliques de maniere enantioselective