Theoretical study on the nucleophilic fluoroalkylation of propylene oxide with fluorinated sulfones

Abstract

The paths of nucleophilic fluoroalkylation reaction of propylene oxide with PhSO2CYF- (Y = F, H, and PhSO2, respectively) in the gas phase and in Et2O solvent were studied theoretically. The nucleophilic fluoroalkylation of propylene oxide with fluorinated carbanions was probed by comparison of the reactivities (phenylsulfonyl)monofluoromethyl anion (PhSO2CHF-), the (phenylsulfonyl)difluoromethyl anion (PhSO 2CF2-), and the bis(phenylsulfonyl) monofluoromethyl anion ((PhSO2)2CF-). The nucleophilicity reactivity order of PhSO2CYF- (Y = F, H, and PhSO2) is (PhSO2)2CF- > PhSO2CHF- > > PhSO2CF2-, which indicates that the introduction of another electron-withdrawing phenylsulfonyl group is an effective way to significantly increase the nucleophilicity of fluorinated carbanions. For comparison, the nucleophilic addition reaction of propylene oxide with the chlorine-substituted carbanion PhSO2CHCl- was investigated. The calculated results show that the nucleophilicity of PhSO2CYF- is better than that of PhSO2CHCl- in the ring opening reaction with propylene oxide. The calculated results are in good agreement with the available experimental ones. Copyright (C)2013 SCS.