Single-Isomer Tetrasubstituted Olefins from Regioselective and Stereospecific Palladium-Catalyzed Coupling of β-Chloro-α-iodo-α,β-unsaturated Esters
作者:Alison B. Lemay、Katarina S. Vulic、William W. Ogilvie
DOI:10.1021/jo060144h
日期:2006.4.1
The efficient regioselective and stereospecific synthesis of tetrasubstituted olefins using a mild and convenient method is disclosed. 2-Alkynyl esters are selectively converted to E-β-chloro-α-iodo-α,β-unsaturated esters by exposure to Bu4NI in refluxing dichloroethane. These products are produced cleanly, regio- and stereoselectively, and in high yields. Single-isomer tetrasubstituted olefins bearing
公开了使用温和且方便的方法有效地区域选择性和立体定向合成四取代的烯烃。通过在回流的二氯乙烷中暴露于Bu 4 NI,将2-炔基酯选择性地转化为E -β-氯-α-碘-α,β-不饱和酯。这些产品是清洁的,区域选择性的和立体选择性的,并且产率高。然后通过顺序的钯催化的偶联反应合成带有四个不同碳取代基的单异构体四取代的烯烃。选择性是由中间底物的反应性差异引起的。