Reactions of N-(Pentafluorophenyl)carbonimidoyl Dichloride with Fluorinated Benzenes in the Presence of AlCl3

Abstract

N-(Pentafluorophenyl)carbonimidoyl dichloride (1) reacts, in the presence of excess AlCl3, with fluorinated benzenes containing 1-5 fluorine atoms in the molecule. With fluoro- and 1,3,5-trifluorobenzene the reaction gives the corresponding imidoyl chlorides and azomethines; at elevated temperatures, azomethines are formed in increased amounts. With 1,2,4,5-tetrafluorobenzene and pentafluorobenzene, intramolecular cyclization, leading to polyfluorinated 1,2,3,4-tetrahydroquinazoline-2,4-diones 9 is preferred. The side reactions are fluorine substitution with chlorine and formation of 1,3-bis(pentafluorophenyl)urea (10).