A Kinetic Study of the Thermal Decarboxylation of alpha,alpha-Difluoro beta-Lactones.
The rates of thermolysis of alpha,alpha-difluoro beta-lactones 1, leading to CO(2) and 1,1-difluoro olefins, have been obtained in the gas phase and in solution, and the activation parameters are reported. Ab initio calculations on the fluoro and nonfluorinated beta-lactone systems are also reported. The gas-phase kinetic and theoretical results are discussed in terms of a probable concerted, asynchronous, nonpolar mechanism, whereas the solution kinetics, which include extensive solvent effect studies, are discussed in terms of a polar mechanism which probably involves formation of a zwitterionic intermediate.
Ocampo
Rogelio
R
Department of Chemistry, University of Florida, Gainesville, Florida 32611, Departamento de Quimica, Universidad de Caldas, Colombia, and Departamento de Quimica, Universidad del Valle, Colombia.
Dolbier
William R.
WR
Bartberger
Michael D.
MD
Paredes
Rodrigo
R