Electrochemical Synthesis of Deuterio Organic Compounds. I. Electrochemical Reduction of 1-Halonaphthalenes and Synthesis of 1-Chloro-4-methylnaphthalene

Electrochemical reduction of 1-chloro-, 1-bromo-, 1-iodo-, 1-chloro-4-methyl-, and 1-bromo-4-methyl naphthalene was done in presence of deuterated water. The deuterium content of the naphthalene obtained reveals that the mechanism for the bromo and the iodo derivatives might involve either a simultaneous transfer of two electrons or an organometallic intermediate, while reduction of the chloro derivative might proceed at least partially via a radical intermediate.The synthesis of 1-chloro-4-methylnaphthalene from 1-chloro-4-chloromethylnaphthalene was achieved either by selective sodium borohydride reduction or by selective electrochemical reduction.