Dealkylation of N,N-dimethylaniline with sulphur and hydrogen sulphide

Abstract N , N -Dimethylaniline successively demethylates at 425 °C in the presence of hydrogen and hydrogen sulphide or sulphur to give successively N -methylaniline and aniline. For the dealkylation reaction, the rank order of promotors is S > S  H 2 > H 2 S > H 2 S  H 2 > H 2 .