Metal carbonyls reaction with arsines

Compounds with a variety of functional groups can be synthesized from arsine oxides by metalation and reaction with electrophilesS subsequent reduction and replacement of the arsenic group by nucleo-philes. Benzothiazoles have been used as versatile carbonyl equivalents, which react under very mild conditions one or two C-branches can be attached stereoselectively and annelation of fused and spiro rings has been described . 

In view of the excellent donor properties of tertiary arsines, it is of interest to inquire whether these cyc/o-polyarsanes can also act as ligands. Indeed, (MeAs)s can displace CO from metal carbonyls to form complexes in which it behaves as a uni-, bi- or triden-tate ligand. For example, direct reaction of (MeAs)5 with M(CO)6 in benzene at 170° (M = Cr, Mo, W) yielded red crystalline compounds [M(CO)3( -As5Me5)] for which the structure... 

Ring expansion is a common result of the reactions of cyclopolyphosphines and arsines with metal carbonyls e.g., Mo(CO)g combines with either cyclo-(MeP)5 or cyclo-(PhAs)g to form [Mo(CO)3]2[>/ , /<-cyclo-(RE)9] whose heavy-atom structure is that of trishomocubane, CnHi4, the same structure as found in and... 

As discussed in Sect. 2.4, the reaction of carbonyl metal clusters with N-oxide trimethylamine may often be a convenient method for synthesizing cluster compounds via ligand substitution. Kinetic studies of the substitution of CO-ligands by phosphines and arsines in group-18 trimetal dodecarbonyls... 

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