Electrophilic additions to unsaturated systems : By P.B.D. De la Mare and R. Bolton,Elsevier Scientific Publ. Co., Amsterdam and New York, 2nd Edition, 1982, xiii + 377 pages,U.S. $91.50, Dutch Fl. 215.00

The metalmetal double-bonded μ-alkyne complex Ru₂(μ-CO)(μ-C₂Ph₂) (η-C₅H₅)₂] (1) reacts with diazomethane at 0°C to yield Ru₂(CO)(η-CH₂) {μ-C(Ph)C(Ph)CH₂} (η-C₅H₅)₂] (2) incorporating two methylene units, one bridging the metal atoms and one linked with the alkyne. Upon heating, a second carboncarbon bond formation occurs to link the methylene groups and give Ru₂(CO)(μ-CO) {μ-C(Ph)C(Ph)C(H)Me} (η-C₅H₅)₂ (3); the structures of 1 and 2 were established by X-Ray diffraction.