高效脱保护ñ - p β支贝里斯-希尔曼加合物的-Toluenesulfinyl集团利用的Amberlite IR-120(加)离子交换树脂
摘要:
的有效的脱保护ñ - p -toluenesulfinyl组β支化的Baylis-希尔曼加合物已经通过在室温下在甲醇溶液中使用的Amberlite IR-120(正)离子交换树脂显影。对于六个实例,已经获得了良好的定量产量。在温和条件下未检测到外消旋作用。该新方法提供了同时的脱保护/纯化,这与简化后处理的溶液相脱保护技术相比具有很大的优势。
Novel Asymmetric C−C Bond Formation Process Promoted by Et2AlCl and Its Application to the Stereoselective Synthesis of Unusual β-Branched Baylis−Hillman Adducts
Ytterbium(III) triflate-catalyzed asymmetric nucleophilic addition of functionalized lithium (α-carbalkoxyvinyl)cuprates to chiral p-toluenesulfinimines (thiooxime S-oxides)
作者:Guigen Li、Han-Xun Wei、Jason D. Hook
DOI:10.1016/s0040-4039(99)00756-x
日期:1999.6
Ytterbium(III) triflate has been found to catalyze anionic additions of functionalized lithium (alpha-carbalkoxyvinyl)cuprates to chiral p-toluenesulfinimines (thiooxime S-oxides) in a cosolvent system (Et2O-CH2Cl2). This new system has made it possible to utilize those p-toluenesulfinimines of low solubility in Et2O as the electrophiles to react with anionic (alpha-carbalkoxyvinyl)cuprates for the asymmetric synthesis of the corresponding beta-mono and beta,beta-disubstituted Baylis-Hillman adducts. Modest yields (51.0-64.4% yield) and good to excellent diastereoselectivities (>90% de) were obtained. (C) 1999 Elsevier Science Ltd. All rights reserved.
Novel Asymmetric C−C Bond Formation Process Promoted by Et<sub>2</sub>AlCl and Its Application to the Stereoselective Synthesis of Unusual β-Branched Baylis−Hillman Adducts
作者:Guigen Li、Han-Xun Wei、Bruce R. Whittlesey、Nassim N. Batrice
DOI:10.1021/jo981976l
日期:1999.2.1
Highly Efficient Deprotection of N-p-Toluenesulfinyl Group of β-Branched Baylis–Hillman Adducts by Using Amberlite IR-120 (Plus) Ion-Exchange Resin
作者:Guigen Li、Sun Hee Kim、Han-Xun Wei
DOI:10.1016/s0040-4020(99)01064-9
日期:2000.1
An efficient deprotection of N-p-toluenesulfinyl group of β-branched Baylis–Hillman adducts has been developed by using Amberlite IR-120 (plus) ion-exchange resin in methanol solution at room temperature. Good to quantitative yields have been obtained for six examples. No racemization was detected under the mild conditions. This new method provides a simultaneousdeprotection/purification, which has
的有效的脱保护ñ - p -toluenesulfinyl组β支化的Baylis-希尔曼加合物已经通过在室温下在甲醇溶液中使用的Amberlite IR-120(正)离子交换树脂显影。对于六个实例,已经获得了良好的定量产量。在温和条件下未检测到外消旋作用。该新方法提供了同时的脱保护/纯化,这与简化后处理的溶液相脱保护技术相比具有很大的优势。