Asymmetric dihydroxylation of disubstituted allenes
摘要:
Asymmetric dihydroxylation of 1,1-disubstituted and 1,3-disubstituted allenes can be used to synthesize chiral alpha-hydroxy ketones. We have also obtained alpha,alpha'-dihydroxy ketones with high enantioselectivity from 1,3-disubstituted allenes. Low conversion of the dihydroxylation of chiral allenes can be used as a kinetic resolution of sterically hindered allenes. (c) 2005 Elsevier Ltd. All rights reserved.
Asymmetric dihydroxylation of disubstituted allenes
摘要:
Asymmetric dihydroxylation of 1,1-disubstituted and 1,3-disubstituted allenes can be used to synthesize chiral alpha-hydroxy ketones. We have also obtained alpha,alpha'-dihydroxy ketones with high enantioselectivity from 1,3-disubstituted allenes. Low conversion of the dihydroxylation of chiral allenes can be used as a kinetic resolution of sterically hindered allenes. (c) 2005 Elsevier Ltd. All rights reserved.
Heteropoly Acid-catalyzed Direct Substitution of 2-Propynyl Alcohols with Sulfonamides
作者:J. S. Yadav、B. V. Subba Reddy、T. Srinivasa Rao、B. Bala. M. Krishna、G. G. K. S. Narayana Kumar
DOI:10.1246/cl.2007.1472
日期:2007.12.5
Directsubstitution of the hydroxygroup in 2-propynyl alcohols with sulfonamides has been achieved using 5 mol % of phosphomolybdic acid supported on silica gel (PMA/SiO2) under mild reaction cond...
Chemoselective Isomerization of Secondary-Type Propargylic Alcohols to Propargylic/Allenic Bromides, and Brominated Dienes with Appel-Type Reaction Conditions
作者:Norio Sakai、Tsukasa Maruyama、Takeo Konakahara
DOI:10.1055/s-0029-1217701
日期:2009.8
Herein is described the chemoselective isomerization of secondary-type propargylicalcohols to allenic bromides, propargylicbromides and brominated dienes under Appel-type reaction conditions containing Ph 3 P, CBr 4 and additives.