Polyfluoroaryl organometallic compounds. Part XVI. Reactions of organolithium compounds with halogenated benzils

Abstract

Reactions of alkyl- or aryl-lithiums with decafluorobenzil gave adducts which undergo rapid pentafluorophenyl migration. A variety of products were obtained after hydrolysis, depending on the lithio-derivative used: ketoalcohols, a benzo[b]furan derivative (from C₆F₅Li), and bis(pentafluorophenyl)methyl pentachlorobenzoate (from C₆Cl₅Li). The mechanisms of these processes are discussed. Some analogous reactions of benzil are described for comparison and relative migratory aptitudes of groups in these processes are examined.