The methylene bases derived from the quaternary salts of various nitrogen heterocyclic compounds have been shown to undergo many reactions characteristic of enamines.'t2 In the case of the methylene base3 derived from 2, 3-dimethylbenzothiazolium salts (1, R= H), elucidation of the course of its reactions has been complicated by the fact that it exists as a dimer. 4 The correct structure 2 of this dimer was first proposed by Larive and ...
