Selective photochemical reduction of carbon-chlorine bond in fluoropropanoates and its quantum yields

Abstract

Ultraviolet light initiated reduction of methyl 2,2,3-trichlorodifluoropropanoate (I), methyl 2,3-dichlorotrifluoropropanoate (II) and methyl 2-chlorotetrafluoropropanoate (III) in 2-propanol afforded methyl 2,3-dichloro-3,3-difluoropropanoate (IV), methyl 3-chloro-2,3,3-trifluoropropanoate (V) and methyl 2,3,3,3-tetrafluoropropanoate (VI) in the respective yields 81%, 86% and 75%. Maximum quantum yields, φmax, of the reduction at 254 nm for the ester IV, V and VI are 225, 240 and 270, respectively, indicating thus a chain reduction mechanism.