钯（II）催化2-炔醇环羰基化反应合成（Z）-α-卤代亚烷基-β-内酯及其后续偶联反应的研究

Studies on Pd(II)-catalyzed synthesis of (Z)-alpha-haloalkylidene-beta-lactones from cyclocarbonylation of 2-alkynols and the subsequent coupling reactions.

作者信息

Ma Shengming, Wu Bin, Jiang Xuefeng, Zhao Shimin

机构信息

State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, P R China.

出版信息

J Org Chem. 2005 Apr 1;70(7):2568-75. doi: 10.1021/jo0480038.

DOI:10.1021/jo0480038

PMID:15787544

Abstract

[reaction: see text] A good regio- and stereoselectivity was observed for the PdCl2-catalyzed cyclocarbonylation of 2-alkynols with CuCl2 affording (Z)-alpha-chloroalkylidene-beta-lactones. The highly optically active (Z)-alpha-chloroalkylidene-beta-lactones could be easily prepared from the readily available optically active propargylic alcohols. The Pd(II)-catalyzed cyclocarbonylation of 2-alkynols with CuBr2 was also studied. Although the yields of (Z)-alpha-bromoalkylidene-beta-lactones were low, due to the relatively higher activity of the C-Br bond, the coupling reactions of (Z)-alpha-bromoalkylidene-beta-lactones were quite smooth to afford the corresponding products in high yields. A rationale for this reaction is discussed.

摘要

[反应：见正文] 观察到在PdCl₂催化下，2-炔醇与CuCl₂进行环羰基化反应时具有良好的区域选择性和立体选择性，生成(Z)-α-氯亚烷基-β-内酯。由易得的旋光性炔丙醇可轻松制备出高光学活性的(Z)-α-氯亚烷基-β-内酯。还研究了Pd(II)催化2-炔醇与CuBr₂的环羰基化反应。尽管(Z)-α-溴亚烷基-β-内酯的产率较低，但由于C-Br键活性相对较高，(Z)-α-溴亚烷基-β-内酯的偶联反应相当顺利，能以高产率得到相应产物。讨论了该反应的原理。