Lewis acid-catalyzed reactions of ethyl diazoacetate with aldehydes. Synthesis of α-formyl esters by a sequence of aldol reaction and 1,2-nucleophilic rearrangement
作者:Shuji Kanemasa、Toshio Kanai、Takahiro Araki、Eiji Wada
DOI:10.1016/s0040-4039(99)00932-6
日期:1999.7
give either β-keto esters or α-formyl esters, the types of products mainly depending upon the nature of Lewis acid catalysts employed. Reactions catalyzed by Lewis acids such as SnCl2 and SnCl4 provide β-keto esters via nucleophilic 1,2-hydride migration, while those catalyzed by trimethylsilyl triflate give α-formyl esters via migration of the substituent of the aldehyde. Reaction mechanisms are discussed
重氮乙酸乙酯在路易斯酸催化剂的存在下与多种醛反应,生成β-酮酸酯或α-甲酸酯,产物的类型主要取决于所用路易斯酸催化剂的性质。路易斯酸如SnCl 2和SnCl 4催化的反应通过亲核1,2-氢化物迁移提供β-酮酯,而三氟甲磺酸三甲基甲硅烷基酯催化的反应则通过醛取代基的迁移得到α-甲酸酯。讨论了反应机理。