In this article we summarize a series of scientific results obtained in recent years through our study on chemical reactions of M-M(M=Mo, W) singly-bonded compounds (η^5-RC5H4)2M2(CO)6, M=M doubly-bonded compounds (η^5-RC5H4)2M2(CO)2(μ-EPh)2(E=S, Se, Te) and M≡M triply- bonded compounds (η^5-RC5H4)2M2(CO)4. These results clearly show that the three types of metal-metal bonded organometallic compounds mentioned above can react with a wide variety of inorganic, organic and organometallic reagents. These studied reactions may involve addition to or cleavage of metal-metal bonds, elimination of the ligands attached to metal-metal bond and/or transformations of the organic functionalities on cyclopentadienyl rings. They are of importance in both theory and practical applications in synthesis of new types of organometallic compounds and cluster complexes.

Key words: MOLYBDENUM, CYCLOPENTADIENYL GROUP, TUNGSTEN, METALLIC BONDS, CHEMICAL REACTION, ORGANIC SYNTHESIS, DINUCLEAR COMPLEX