Sodium Bicarbonate-Catalyzed Stereoselective Isomerizations of Electron-Deficient Propargylic Alcohols to (<i>Z</i>)-Enones
作者:John P. Sonye、Kazunori Koide
DOI:10.1021/jo0623944
日期:2007.3.1
Redoxisomerization is a synthetically important process because it creates two new functional groups in the product, among which is the isomerization of propargylic alcohols to conjugated enones. Although E-enones have been prepared by this approach, Z-enones could not be accessed. We previously reported DABCO-catalyzed E-selective isomerization of electron-deficient propargylic alcohols to enones
Dinuclear Zn-Catalyzed Asymmetric Alkynylation of Unsaturated Aldehydes
作者:Barry M. Trost、Andrew H. Weiss、Axel Jacobi von Wangelin
DOI:10.1021/ja054871q
日期:2006.1.1
Our recent development of a proline-derived bimetallic catalyst has led to a number of efficient, catalytic, enantioselective transformations. Herein, we report a practical and general alkynylation of aromatic and alpha,beta-unsaturated aldehydes using our zinc catalyst system.
Highly enantioselective catalytic methyl propiolate addition to both aromatic and aliphatic aldehydes
作者:Jian Huang、Siping Wei、Li Wang、Chun Zhang、Shuangxun Li、Pingxian Liu、Xi Du、Qin Wang
DOI:10.1016/j.tetasy.2016.03.009
日期:2016.6
The excellent catalytic effect on methyl propiolate addition to a wide range of aromatic and aliphatic aldehydes promoted by inexpensive and commercially available BINOL-based ligand is reported. The catalyst systems showed high yields and excellent enantioselectivities for aromatic aldehydes, and excellent yields and high enantioselectivities for aliphatic aldehydes. (C) 2016 Elsevier Ltd. All rights reserved.
A Mild Method for the Preparation ofγ-Hydroxy-α,β-Acetylenic Esters
作者:Shatrughan P. Shahi、Kazunori Koide
DOI:10.1002/anie.200353400
日期:2004.5.3
Base-Catalyzed Stereoselective Isomerization of Electron-Deficient Propargylic Alcohols to <i>E</i>-Enones
作者:John P. Sonye、Kazunori Koide
DOI:10.1021/jo060304p
日期:2006.8.1
stereoselective methods to isomerize electron-deficient propargylic alcohols to E-enones under mild conditions (EWG = electron-withdrawing group). Among weak bases we screened, catalytic (10−20 mol %) 1,4-diazabicyclo[2.2.2]octane (DABCO) was found to be effective in most cases. When the substrate is conjugated with an amide, the addition of sodium acetate catalyzed the isomerization.