One-Carbon Ring Expansion of Azetidines via Ammonium Ylide [1,2]-Shifts: A Simple Route to Substituted Pyrrolidines
作者:Tina M. Bott、John A. Vanecko、F. G. West
DOI:10.1021/jo9001323
日期:2009.4.3
diazocarbonyl compounds in the presence of catalytic Cu(acac)2 to furnish substituted pyrrolidines via Stevens [1,2]-shift. In all but two examples, complete selectivity was seen for ring expansion rather than migration of the other exocyclic group on the azetidinium nitrogen. The two exceptions, observed with ylidessubstituted with two carbonyl groups and lacking a stabilizing group at the 2-position