Organomercury compounds dimerization

Irradiation of phenyliodonium salts lead to the formation of phenyl radicals. In the presence of C60 these radicals are efficiently trapped under formation of pheny-lated C6o derivatives, mainly the monoadduct. In reaction mixtures of C6o, phenyliodonium salts and spin traps like nitroso-tert-butane ( BuNO) or nitroso-durene (ND) no phenyl adducts with the spin traps could be observed after irradiation. This suggests that C6o is a more efficient scavenger for phenyl radicals than the spin traps [177], Other investigations yielded similar results, e.g., the photolysis of organomercury compounds in the presence of fullerenes leads to fullerene-derived radical adducts. These radical adducts can combine to form dimers that are thermally stable and accumulate in the samples [Eq. (7)] [178],... 

The activation entropy for thermal decomposition of /ra j -[MnX(CO)3(PPh3)2] indicates that manganese-phosphorus bond breaking is rate-determining. The rate law for the decomposition of CoH(CO)4 to Co2(CO)8 plus hydrogen is second-order in cobalt compound. While this decomposition has previously been studied in the gas phase, this is the first report of decomposition kinetics in the liquid phase. The first step in reaction of Co2(CO)s with organomercury halides is solvent-induced disproportionation of the dimeric carbonyl. ... 

Organomercury dithiophosphinates are self-assembled supramolecular species. Thus, the dimeric [MeHgS2PPh2]2 and self-assembled [PhHgS2PEt2)2]x/ both are formed through intermolecular Hg- S secondary bonds. A cyclomet-allated mercury compound, ArHg(S2PCy2) (Ar = 2-(2-pyridyl)phenyl) is monomeric owing to the formation of an internal N Hg dative bond. ... 

A series of reactions of [Et3NHl+[Fe2(CO)6( X CO)(n-SR)]- with alkynylmercury compounds was found to give different products depending on the nature of the organomercurial. X-ray crystal structure determinations on the vinyl carbyne complex [Fe2(CO)6(p-MeOCH=CHC)(p-SBu )] and the dimeric mercury product [ Fe2(CO)6(p-MeOCH2CH=CHC)(p-SBu ) 2Hg] were reported. 

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