ORGANOSELENIUM CHEMISTRY - DEALKYLATION OF AMINES WITH BENZENESELENOL

Spectroscopic studies of alkylamine-benzeneselenol mixtures show that complete or almost complete proton transfer to form an ammonium selenolate salt occurs. Pyrolysis of these salts or solutions of them results in nucleophilic dealkylation of the amine if an alkyl group susceptible to SN2 displacement is present. Products are the dealkylated amine and an alkyl phenyl selenide. Primary amines are dealkylated least and hindered tertiary amines most rapidly. Benzenethiol does not protonate alkylamines, although a salt does form with l, 8-bis(dimethylamino)naphthalene (4). Competitive studies show that PhSe- is at least a factor of 5 more nucleophilic than PhS- but that PhS- will demethylate PhSeCH3 at a rate comparable to its reaction with protonated 4. © 1979, American Chemical Society. All rights reserved.