Preparation of Phosphine Complexes

Organophosphine complexes can often be made simply by mixing stochiometric quantities of a metal salt and phosphine ligand (8.55) and (8.56). Displacement reactions are also used (8.57). These generally lead to a series of derivatives of which the final product represents complete replacement (8.58). 

Higher metal coordination can sometimes be acheived by exchange (8.59) or simple addition (8.60) and (8.61) (see 8.637). 

Sometimes the solvent can serve as a source of a carbonyl ligand as with ethylene glycol in (8.63). Alkyl may be converted into acyl (8.65), aldehydes added (8.64) or reductive elimination carried out (8.66). A complex with high oxidising power can be obtained with Au powder (8.67), 

Some crystalline complexes will yield the original phosphine on heating, in which case they may be useful for purification purposes. Thus pure trimethylphosphine may be obtained from [Me3P Agll,. 

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