REACTION OF THE IN-SITU-GENERATED RUTHENIUM-ACETYLIDE COMPLEX C5ME5RU(PPH3)C-CPH WITH SMALL MOLECULES

A coordinatively unsaturated acetylide species C5Me5Ru(PPh3)C=CPh (1) was generated in situ from the reaction of ruthenium-vinylidene comple x C5Me5Ru(Cl)(PPh3)=C=CHPh (2) with Et3N. The vinylidene complex 2 was prepared from the substitution. reaction of C5Me5Ru(PPh3)(2)Cl with P hC=CH. The in-situ-generated 1 was found to react readily with a varie ty of small molecules. For example, the reaction of 1 with CO produced the stable adduct C5Me5Ru(CO)(PPh3)C=CPh (3) in 85% yield, the struct ure of which was established by X-ray crystallography. The similar rea ctions of 1 with H-2 and PhC=CPh also gave the hydride complex C5Me5Ru (PPh3)(H)(H2C=CHPh) (4) (76% yield) and the alkyne complex C5Me5Ru(PPh 3)(PhC=CPh)C=CPh (5) (85% yield), respectively. The reaction of 1 with CO2 produced the carboxylate complex C5Me5Ru(PPh3)(eta(2)-O2CC=CPh) ( 6) from the insertion of CO2 to the ruthenium-acetylide carbon bond.