摘要:
The reactivity of ammonium- and iminium-BPh4 Salts, [CH2=CHCH2NH3]BPh4, [(CH2=CHCH2)HN=CMe2]BPh4 and [(PhCH2)HN=CMe2]BPh4, towards Pd(0)-complexes, [Pd(dppe)(dba)] and [Pd(dppe)(2)] (dppe = 1,2-bis(diphenylphosphino)ethane; dba = dibenzylideneacetone), has been investigated. Allyl-ammonium and -iminium tetraphenylborates [CH2=CHCH2NH3]BPh4 and [(CH2=CHCH2)HN=CMe2]BPh4 react with [Pd(dppe)(dba)] to afford, under mild conditions (293 K), [(eta(3)-C3H5)Pd(dppe)][BPh4], through selective oxidative transfer of allyl group from the ammonium or iminium cation to the Pd center. [(PhCH2)HN CMe2]BPh4 reacts with [Pd(dppe)(2)] to afford [H-Pd(dppe)(2)][BPh4], that, under the reaction conditions, has poor stability as it undergoes hydride transfer to the iminium ion present in the reaction medium, affording [Pd(dppe)(2)][BPh4](2). (C) 2002 Elsevier Science B.V. All rights reserved.