Reactions of diarsines with bi- and tri-metallic carbonyl complexes containing cobalt

Abstract

Reaction of the diarsines As2R4 (R = Me or Ph) with alkyne-bridged dicobalt hexacarbonyl complexes leads to products with bridging (AsR2)2O ligands and to the production of simple AsR3 substituted complexes; alkylidyne tricobalt nonacarbonyl complexes exhibit parallel reactivity with As2R4. Thermolysis of the complex [Co2(μ-PhCCPh){μ-(AsMe2)2O}(CO)4] gives the tetra-substituted complex, [Co2(μ-PhCCPh){μ-(AsMe2)2O}2(CO)2]. Reaction of the heterometallic complex [(OC)3Co{μ-C2(CO2Me)2}MoCp(CO)2] with As2Ph4 affords [{(HO)Ph2As}(OC)2Co{μ-C2(CO2Me)2}MoCp(CO)2], supporting the suggestion of a possible hydrolytic mechanism for the formation of the (AsR2)2O bridged complexes.