Reactions of Complexes with Neutral Carbene Precursors

In order to explain reactions of diazomethane and its derivatives with coordination compounds, it has been proposed that the formation of intermediate carbene complexes takes place. In the reaction of bis(trifluoromethyl)diazomethane with [IrCl(CO)(PMePh2)2] the carbene complex [IrCl(CO)(PMePh2)2 C(CF3)2 ] is formed rather than the chlorobis(trifluoromethyl)methyl iridium complex Ir CCl(CF3)2 (CO)(PMePh2)2. In many cases, such complexes were isolated and investigated  

Electron-rich alkenes react with transition metal compounds with cleavage of the carbon-carbon double bond to afford carbene compounds. 

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