Mechanisms of halocarbene additions to cyclooctyne: An experimental and theoretical investigation

ORGN 95

Sarah Bernard, Denise Napolitano, Kaitlyn Suski, Marina Khrapunovich, and Dina C. Merrer, dmerrer@barnard.edu. Department of Chemistry, Barnard College, 3009 Broadway, New York, NY 10027
Wittig and Hutchison reported the unique mechanisms of CH2, CPh2, CCl2 and CMe2 additions to cyclooctyne 35 years ago. Our recent (2005) research on the intervention of nonstatistical dynamic effects on dihalocarbene additions to cyclopropenyl systems has led us to a reinvestigation of the mechanism of halocarbene (RCCl, R = Ph, Cl) additions to cyclooctyne. Our experimental and computational studies have found the barriers to the addition of RCCl to cyclooctyne to be negligible, and to lead to several reaction paths terminating in distinct products.