Janus‐Faced Aluminum: A Demonstration of Unique Lewis Acid and Lewis Base Behavior of the Aluminum Atom in [LAlB(C₆F₅)₃]

Abstract

Some elements go both ways: The reaction of [LAl] (L=HC(CMeNAr)2, Ar=2,6-iPr2C6H3) with BArF3 (ArF=C6F5) yields [LAlBArF3] (see scheme). Crystallographic studies and ab initio calculations show the formation of an AlF bond, which shows the aluminum center having both Lewis base and Lewis acid character.