PROTON ABSTRACTION AND ELECTROPHILIC QUENCH AT C-2 OF IMIDAZOLIDINES

Imidazolidines bearing tert-butoxycarbonyl groups on both nitrogen ato ms have been prepared in order to test their ability to act as acyl an ion equivalents. Proton abstraction was achieved successfully at C-2, between the two nitrogen atoms, using the base sec-butyllithium. The r esulting organolithium was trapped with a variety of electrophiles. Th e imidazolidine can be cleaved with acid to generate the desired carbo nyl compound. Using chiral imidazolidines and aldehyde electrophiles, the carbon-carbon bond formation occurred with low diastereoselectivit ies. (C) 1998 Elsevier Science Ltd. All rights reserved.