Treatment of tertiary alkyl fluoride with diphenylphosphine in the presence of a stoichiometric amount of boron trifluoride etherate yields the corresponding tert- alkyldiphenylphosphine despite the coexistence of the strong Lewis acid and the highly coordinating phosphine. Use of diphenyl (trimethylsilyl) phosphine as a nucleophile makes the reaction catalytic in boron trifluoride.
