Abstract Three-component Mukaiyama–Mannich reaction of aldehydes, amines, and silyl enol diazoacetoacetate was efficiently carried out to afford δ-amino substituted-α-diazoacetoacetate derivatives catalyzed by 5 mol% of MgI2 etherate (MgI2•(OEt2)n) under mild and neutral reaction conditions in good to excellent yields. GRAPHICAL ABSTRACT
Catalytic Addition Methods for the Synthesis of Functionalized Diazoacetoacetates and Application to the Construction of Highly Substituted Cyclobutanones
作者:Michael P. Doyle、Kousik Kundu、Albert E. Russell
DOI:10.1021/ol052003s
日期:2005.11.1
[reaction: see text] Methyl 3-(trialkylsilanyloxy)-2-diazo-3-butenoate undergoes Lewis acid-catalyzed Mukaiyamaaldol addition with aromatic and aliphatic aldehydes in the presence of low catalytic amounts of Lewis acids in nearly quantitative yields. Scandium(III) triflate is the preferred catalyst and, notably, addition proceeds without decomposition of the diazo moiety. Diazoacetoacetate products