Phosphine complexes of rhenium

The most important complexes of rhenium(I) are those containing the dinitrogen ligand, in which the rhenium atom is also complexed by phosphine ligands. 

Most complexes of this oxidation state are derivatives of the rhenium(III) halides. They are classified according to the other ligands (if any) that are present. For example, ReChfPRjlj will be found under phosphine complexes rather than halide complexes . Mononuclear complexes of rhenium(III) are mostly of the types [ReX2L4]" and ReXjL, but rarely [ReX4L2] . Additionally, two very important classes of complexes exist that are derivatives of the quadruply bonded dinuclear [RcjXg] and doubly bonded trinuclear [RejX,2] anions (X = Cl, Br or I). ... 

Octahedral complexes of rhenium(V), rhenium(lll), and rhenium(Il) derived from ditertiary phosphines have been prepared by reaction of the phosphine with potassium perrhenate or rhenium heptoxide in the presence of a halogen acid and an organic solvent. These include complexes of the types [(RjPCHjCH PRj) ReO/x , [(R PCH CH PRp ReXjj+X- and [(R PCH CH PRp eX ] where R or CH and X = Cl. Br, or I. 

Zero-valent complexes of rhenium have been prepared by reacting dirhenium decacarbonyl with mono- and ditertiary phosphines and amines in the presence of an organic solvent, hear or UV light can be used to produce reaction. 

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