Synthesis of 1-Acyl-2-vinylcyclopropanes: Utilizing Copper-Carbenoid versus Sulfur Ylide Methodology

The synthesis of a range of racemic 1-acyl-2-vinylcyclo­propanes by using two different methodologies is studied. We have developed a copper-catalyzed process for converting diazoketones into 1-acyl-2-vinylcyclopropanes and a sulfur-ylide-mediated procedure which allows, in only two steps, a simplified access to 1-acyl-2-vinyl­cyclopropanes with alkyl or aryl substituents on the alkene moiety.