Reaction of Chlorosulfonyl Isocyanate with Fluorosubstituted Alkenes: Evidence of a Concerted Pathway
作者:Dale F. Shellhamer、Kevyn J. Davenport、Danielle M. Hassler、Kelli R. Hickle、Jacob J. Thorpe、David J. Vandenbroek、Victor L. Heasley、Jerry A. Boatz、Arnold L. Reingold、Curtis E. Moore
DOI:10.1021/jo101240s
日期:2010.11.19
Concerted reactions are indicated for the electrophilic addition of chlorosulfonylisocyanate with monofluoroalkenes. A vinyl fluorine atom on an alkene raises the energy of a stepwise transition state more than the energy of the competing concerted pathway. This energy shift induces CSI to react with monofluoroalkenes by a one-step process. The low reactivity of CSI with monofluoroalkenes, stereospecific
more efficient than the bimolecular reaction of the dissociated reagents above room temperature. This finding provides a method for improving the reactions of CSI with unreactive alkenes. Chlorosulfonylisocyanate (CSI) is a sluggish electrophile in reactions with electron-deficient alkenes or with many monofluoroalkenes. The efficiency of these reactions is improved at temperatures between –15 and