Synthesis of functionalized naphthalenes

1,2 and 2,3-disubstituted naphthalenes were synthesized by carbene addition to substituted indenes. The indene precursors were formed by two methods: Grignard addition to indanones with elimination and by the reaction of indanones with phosphorus pentahalide. The carbene addition to indene was facilitated fcy the use of a micellar phase transfer catalyst, hexadecyltrimethyl ammonium branide. This catalyst allowed carbene addition to double bonds with both electron donating and withdrawing substituents. The naphthalenes formed by this method include: 2-chloro-3-methylnaphthalene, 2-chloro-3-phenylnaphthalene, 1,2-dichloronaphthalene, 2-chloro-l-phenylnaphthalene, 2-brano-3chloronaphthalene and 2,3-dichioronaphthalene