Cobalt-catalyzed annulation of styrenes with α-bromoacetic acids
作者:Tung T. Nguyen、Bao H. T. Ngo、Huy X. Le、Linh N. P. Vu、Tuong A. To、Anh N. Q. Phan、Nam T. S. Phan
DOI:10.1039/d0ra09588e
日期:——
We report a method for addition of α-bromophenylacetic acids to vinyl CC bonds in styrenes to afford γ-lactones. Reactions employed a simple cobalt catalyst Co(NO3)2·6H2O in the presence of dipivaloylmethane (dpm) ligand. Many functionalities including halogen, ester, and nitro groups were compatible with reaction conditions. If α-bromoesters were used, vinylacetates were the major products.
我们报告了一种将 α-溴苯乙酸添加到苯乙烯中的乙烯基 C C 键以提供 γ-内酯的方法。在二戊酰甲烷 (dpm) 配体存在下,反应使用简单的钴催化剂 Co(NO 3 ) 2 ·6H 2 O。许多官能团,包括卤素、酯和硝基,都与反应条件相容。如果使用 α-溴代酯,醋酸乙烯酯是主要产品。
Efficient Addition of Acid Enediolates to Epoxides
作者:Salvador Gil、Mercedes Torres、Natalia Ortúzar、Richard Wincewicz、Margarita Parra
DOI:10.1002/ejoc.200300795
日期:2004.5
We report new conditions to facilitate the addition of dianions of carboxylic acids to epoxides as an alternative method to the use of aluminum enolates. These conditions require the use of a sub-stoichiometric (10%) amount of amine for dianion generation and the previous activation of the epoxide with LiCl. Other Lewis acids have been shown to be less effective. Yields are good but only low diastereoselectivity
Metal-Catalyst-Controlled Divergent Synthesis of γ-Butyrolactones via Intramolecular Coupling of Epoxides with Alcohols
作者:Feipeng Liu、Zifan Cheng、Yiyun Fang、Xuchao Wang、Lingzi Zhao、Zi-Qiang Rong
DOI:10.1021/acs.orglett.3c00898
日期:2023.5.26
A metal-controlled divergent protocol for the synthesis of α- and β-substituted γ-butyrolactones was developed through intramolecular coupling of epoxides with alcohols. This method provides an efficient and practicable way to afford γ-butyrolactones with good efficiency, excellent regioselectivity, and broad substrate scope.