Gold(I)-Bis(diphenylphosphino)amid und einige Gold(I)-Bis(diarylphosphino)methanide mit sterisch anspruchsvollen Arylsubstituenten / Gold(I)-bis(diphenylphosphino)amide and Some Gold(I)-bis(diarylphosphino)methanides with Bulkyl Aryl Substituents

Abstract

Intensely yellow coloured, insoluble gold(I)-bis(diarylphosphino)amides, [(C 6 H 5 )P 2 NAu, 1, is obtained from lithiated bis(diphenylphosphino)amine and AuCl complexes of tertiary phosphines. 1 is assigned a dimeric eightmembered ring structure on the basis of its 197 Au-Mößbauer spectrum and of a direct analogy with the corresponding bis(phosphino)methanide complexes, whose structure has recently been confirmed by X-ray diffraction. A series of mono- and binuclear AuCl complexes of bis(diarylphosphino)methanes bearing bulky 2-tolyl or 2,6-dimethylphenyl substituents (3a, b) was synthesized from the diphosphines and (CO)AuCl in the molar ratios 1:2 or 1:1. The compounds have structures 4 a, b and oa, b, respectively. An ionic tetrafluoroborate derivative 6 b was obtained from the chloride 5 b on treatment with AgBF 4 . Lithiation of the diphosphinomethanes 3 a, b using LiCH 3 followed by reaction with CIAuPR 3 complexes yields the deep-yellow Au(I) bis(diarylphosphino)methanides 7 a, b. All compounds, including the new ligand 3b and its precursor (2,6-(CH 3 ) 2 C 6 H 3 )2PBr, 2, were characterized by analytical and spectroscopic data.