Bridged phosphine complexes manganese

Complexity in the manganese and rhenium pentarbonyl halides substitution arises from the fact that these decompose in inert solvents to form the halogen-bridged dimers [M(CO)4X]2. Both monomers and dimers react with phosphines, arsines, pyridine, aniline etc. to give the disubstituted compounds M(CO)3XL2. Thus three final products or any mixture of them may be obtained, depending upon the precise reaction conditions... 

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