Halogenation with rhenium complexes

In reactions of halogens with substituted rhenium carbonyl halides, the compounds ReX(CO) (diars)2 [X = Br, I diars = l,2-C6H4(AsMe2)2] and bromine or iodine in chloroform give the complexes [ReX2(CO) (diars)2]X3 ... 

N-halosucdnimides (chloro-, bromo-, and iodo-) are useful reagents for oxidations in organic chemistry and for the oxidative halogenation of metal complexes. For example, the reaction of the rhenium hydride, trans-(H,Br)-[Re(Bt)(FO(CO)(PMe Cp l with N-hromosucdnimide in THF at 0 C... 

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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