Reactions of trichloromethyl anions with diformylbenzenes. Estimation of Hammett substituent constants of the formyl, trichloroacetyl, and 2,2,2-trichloro-1-hydroxyethyl groups

Abstract

o- and p-diformylbenzenes react at room temperature with trichloroacetic acid in dimethyl suiphoxide to yield insoluble products corresponding to the addition of trichioromethyl anion to carbonyl groups. The addition of one ^–CCl₃ ion to the o-isomer leads to the formation of a cyclised phthalan product. The Hammett σ_p constants of the groups CHO, CH(OH)CCl₃, and COCCl₃ have been estimated as 0.40, 0.32 and 0.70 respectively.