Expedient preparation of halogenocyclopropanes by stereoselective cyclopropanation of electron-deficient allylic ethers

ORGN 663

André B. Charette and Marie-Christine Lacasse. Département de Chimie, Université de Montréal, P.O. Box 6128, Station downtown, Montréal, QC H3C 3J7, Canada

In our continuing studies of the Simmons-Smith cyclopropanation, we have recently reported that the reaction of chiral acyclic allylic ethers with a trifluoroacetic acid-derived zinc carbenoid (CF3CO2ZnCH2I) proved to be a new and expedient way to access anti-cyclopropylcarbinol derivatives. We now expand the scope of this methodology to electron-deficient allylic alcohols and ethers using our previously optimized conditions. Thus, p-EWG-phenyl- and halogeno-cyclopropylcarbinol derivatives can be synthesized stereoselectively in a simple, preparatively useful manner. The yields obtained range from modest to excellent with generally high selectivity in favor of the anti diastereomer.

New Reactions and Methodology 8:00 AM-12:00 PM, Thursday, March 27, 2003 Convention Center -- Room 296, Oral Division of Organic Chemistry The 225th ACS National Meeting, New Orleans, LA, March 23-27, 2003