Phosphino-Boryl-Naphthalenes: Geometrically Enforced, Yet Lewis Acid Responsive P → B Interactions

Abstract

Three naphthyl-bridged phosphine-borane derivatives <b>2</b>-BCy₂, <b>2</b>-BMes₂, and <b>2</b>-BFlu, differing in the steric and electronic properties of the boryl moiety, have been prepared and characterized by spectroscopic and crystallographic means. The presence and magnitude of the P → B interactions have been assessed experimentally and theoretically. The naphthyl linker was found to enforce the P → B interaction despite steric shielding, while retaining enough flexibility to respond to the Lewis acidity of boron