PHOTOINDUCED REARRANGEMENTS OF RING-COUPLED BIS(CYCLOPENTADIENYLRUTHENIUMDICARBONYL) COMPOUNDS OF THE FORM RU-2(CO)(4)(ETA(5),ETA(5)-C(5)H(4)LC(5)H(4)) (L=CH2, (CH3)(2)C, C2H4 AND (CH3)(2)SI) - THE MOLECULAR-STRUCTURE OF (2)][RU(CO)(2)CL](ETA(5),ETA(5)ETA(1)-C5H4CH2C5H3)

Compounds of the general form Ru-2(CO)(4)(eta(5),eta(5)-C(5)H(4)LC(5)H (4)), where L = CH2-, (CH3)(2)C-, C2H4- and (CH3)(2)Si-, have been fou nd to undergo photolysis in deuterobenzene or deuterotoluene to give ' twisted' ruthenium hydride complexes of the form (CO)(2)H](eta(5),eta( 5):eta(1)-C(5)H(4)LC(5)H(3)). Reaction of these hydrides with chloroca rbons resulted in the formation of the corresponding chlorides which c ould be isolated and characterized by IR, H-1 and C-13 NMR, mass spect rometry, and elemental analysis. In the particular case of Ru-2(CO)(4) [eta(5),eta(5)-C5H4(CH3)(2)SiC5H4] a secondary photochemical reaction occurs with formation of u-eta(5):eta(1)-C5H4)[mu-(CH3)(2)Si-(eta(5)-C 5H4)] in which Ru-Ru and Cp-Si bonds have been broken and new Ru-Cp an d Ru-Si bonds formed. The molecular structure of 2)][RU(CO)(2)Cl](eta( 5),eta(5):eta(1)-C5H4CH2C5H3) was determined by X-ray crystallography: monoclinic, Cc, a = 27.636(5) Angstrom, b = 9.058(2) Angstrom, c = 14. 545(5) Angstrom, beta = 120.85(3)degrees, V = 3126(2) Angstrom(3), Z = 8, R(F)= 2.29%.