Gassman reaction

What is Gassman reaction?

The Gassman reaction, first reported by Gassman in 1972, is a multistep process for preparing ortho-alkylated anilines. Gassman reaction involves sequential treatment of the anilines with tert-butyl hypochlorite, dialkylsulfide, and triethylamine followed by Raney nickel desulfurization, although it is considered a one-pot reaction.

Gassman reaction - general reaction scheme
Gassman reaction

The Gassman reaction can be adapted to prepare anilines with various groups at the ortho-position, such as vinyl, formyl, and benzyl groups, and even para-substituted anilines through a modified process involving N-t-butyl-N-chloro anilines and a nucleophile.

Anilines containing alkyl, vinyl, formyl, and benzyl groups at the ortho-position have been synthesized using Gassman reaction.


Paul G. Gassman, Gordon Gruetzmacher, Richard H. Smith (1972The synthesis, thermolysis and base-catalyzed rearrangement of azasulfonium salts. Tetrahedron Letters, 13(6), 497-500
DOI: 10.1016/S0040-4039(01)84360-4