Formation of 1,4-diphosphinobenzenes via tele-substitution on fluorobenzenechromium complexes

The meta–tele-substitution of 2-(boranatophosphino)fluorobenzenechromium complexes took place with various lithiated secondary phosphine–boranes as nucleophiles to give para-substituted bis(boranatophosphino)benzenechromiums. It was revealed that the yield of the tele-substitution product was strongly affected by the strength of a proton acid. Isotope labeling experiments indicated that 1,5-hydrogen migration was involved in this transformation.