New Synthesis of Mono-Halogenated Adamantanes

A variety of direct halogenations on the adamantane skeleton have been reported. For example, bromination of adamantane with bromine, which is considered to proceed through an ionic mechanism, gives high yield of 1-broinoadamsntane. In contrast to the ionic bromination of adamantane, chlorinations are much less selective^2,3,4,5. Photochloroadamantane of adamantane gives l-chloroadamntane and 2-chloroadamantane. Chlorination with t-butyl chloride in the presence of A1C1₃ gives rise to a mixture of 1-chloroadamantane and 1,3-dichloroadamantane.