Synthesis of carborane-fused carbo- and heterocycles via zirconacyclopentane intermediates

Abstract

A variety of carborane-fused carbo- and heterocycles were prepared in good to high isolated yields via the reaction of carborane-fused zirconacyclopentane with a series of substrates such as S₈, Se, Te, CO, XylNC, MeOOC–CHN₂, PhPCl₂, ⁿBu₂SnCl₂ and Me₂GeCl₂. However, it was found that the Zr–C bond in the zirconacyclopentane did not show any reactivity towards PhBCl₂, PhCN and PhCHNPh. This approach represents a promising route to functionalized carboranes that are difficult to access by conventional methods.