Reaction of Lithium Aluminum Hydride with Methylenebenzanthrene

South Carolina State College, Orangeburg, South Carolina 29117

Manuscript received 22 September 1975; accepted 16 January 1976

The relatively stable benzenoid odd-alternant ions formed by attack of hydride from LiAIH₄ at the ezocyclic carbon accounts for the unusual reactivity of methylenebenzanthrene. The enhanced reactivity of methylenebenzanthrene is reflected in HMO calculations : atom-atom polarizabilities of the ezocyclic carbon atoms are unusually high, and localization energies are quite low compared to other aryl olefins. We report here the first instance of a facile reaction of LiAIH₄ with an alternant hydrocarbon, namely the conversion of methylenebenzanthrene to 7-methylbenzanthrenyl lithium.