Catalytic Double Carbonylation of Epoxides to Succinic Anhydrides: Catalyst Discovery, Reaction Scope, and Mechanism
作者:John M. Rowley、Emil B. Lobkovsky、Geoffrey W. Coates
DOI:10.1021/ja066901a
日期:2007.4.1
The first catalytic method for the efficient conversion of epoxides to succinic anhydrides via one-pot double carbonylation is reported. This reaction occurs in two stages: first, the epoxide is carbonylated to a beta-lactone, and then the beta-lactone is subsequently carbonylated to a succinic anhydride. This reaction is made possible by the bimetallic catalyst [(ClTPP)Al(THF)2]+[Co(CO)4]- (1; ClTPP
报道了通过单锅双羰基化将环氧化物有效转化为琥珀酸酐的第一种催化方法。该反应分两个阶段进行:首先,环氧化物羰基化为 β-内酯,然后 β-内酯随后羰基化为琥珀酸酐。该反应通过双金属催化剂 [(ClTPP)Al(THF)2]+[Co(CO)4]- (1; ClTPP = meso-tetra(4-chlorophenyl) porphyrinato; THF = 四氢呋喃) 成为可能,它是对环氧化物和内酯羰基化具有高活性和选择性,并通过鉴定促进这两个阶段的溶剂。该催化剂与具有脂肪族、芳香族、烯烃、醚、酯、醇、腈和酰胺官能团的取代环氧化物相容。双取代和对映体纯的酸酐由环氧化物合成,具有出色的立体化学纯度保留。通过原位红外光谱研究了环氧化物与 1 的双羰基化机制,这表明两个羰基化阶段是连续的且不重叠的,因此环氧化物羰基化在任何中间体 β-内酯被消耗之前就完成了。环氧化物和内酯羰基化的速率都与一氧化碳压力无关,并且在浓度为