Tetrahedral, Chelated Au I Diphosphine Complexes

The crystal structure of [Au2dppm2Cl2] showed an 8-membered AU2P4 ring  

X = optically-active anion optical isomers not resolved 

In the early 1980 s the existence of tetrakis (monophosphine)Au(I) complexes began to be estabUsbed. Complexes of the type [Au(PR3)4]X were isolated and characterised for the ligands PMes PPha and PMePh2 P NMR solution studies of gold(I) monophosphine complexes in the presence of free PR3 demonstrated that complexes with different Au P ratios undergo rapid ligand exchange above 213 

Four-coordinate complexes were not formed for very bulky phosphines such as P(C6Hu)3, P U3, P Bu2Ph and PPrjPh. 

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