Observations on the direct amidocyclopropanation of alkenes using organozinc carbenoids

A series of amidocyclopropanes were prepared by direct amidocyclopropanation of alkenes, using organozinc carbenoids generated from readily available diethoxymethylamides. The amidocyclopropanation of monosubstituted alkenes led to selective formation of the trans-amidocyclopropane in most cases, but with more substituted alkenes, the stereochemical outcome of the cyclopropanation reactions was unpredictable. The amidocyclopropane products can be readily elaborated to structurally interesting cyclopropane containing amino acids or amino alcohols. (c) 2007 Elsevier Ltd. All rights reserved.