The kinetics and mechanisms of aromatic halogen substitution. Part XXV. The chlorination of 2-methylnaphthalene

Abstract

The chlorination of 2-methylnaphthalene in acetic acid is generally similar to that of naphthalene, in that products of substitution are accompanied by those of addition. The main components of the reaction mixture have been separated, and the structures of a crystalline tetrachloride, m.p. 99–99·5°, and of an acetoxytrichloride, m. p. 130°, have been deduced from studies of their proton magnetic resonance spectra and of their behaviour on alkaline dehydrochlorination. Their properties are compared with those of a 1-chloro-2-methylnaphthalene tetrachloride, m. p. 153°, and of various related compounds. The synthesis of 1,4-dichloro-2-methylnaphthalene is described.