Structural studies of the hydrazine and ammine complexes of the dinuclear ruthenium polysulfide complexes

The dinuclear ruthenium polysulfide complex, [Ru-2(II)(mu-S-n)(mu-S2CNMe2)(S2CNMe2)(CO)(2)(PPh3)(2)] (1). 0.5CH(2)Cl(2) (n = 5 or 6), was reacted with N-donor ligands, hydrazine, ammonia, and pyridine. The reaction of hydrazine with 1.2 equiv of 1.0.5CH(2)Cl(2) affords the crystallographically characterized dinuclear Ru-II complex, {[Ru-II(S-2-CNMe2)(Co)(PPh3)](2)(mu-S-4)(mu-N2H4} (2) 0.5CH(2)Cl(2). The octahedrally coordinated Run centers are doubly bridged by N2H4 and the S-4 chain. The S-4 chain is formed through a desulfurization reaction of the S-n (n = 5 or 6))ligand in 1. The reaction yield was improved in the presence of one equiv of PPh3. The space group and the cell data for 2 . 0.5CH(2)Cl(2) are as follows: triclinic, space group P (1) over bar (No. 2) with a = 20.003(3) Angstrom, b = 14.155(2) Angstrom, c = 10.061(2) Angstrom, alpha = 110.70(1)degrees, beta = 90.73(1)degrees, gamma = 104.23(1)degrees, V = 2567.4(8) Angstrom(3), and Z = 2. The dinuclear ruthenium pentasulfide [Ru-2(II)(mu-S-5)(mu-S2CNMe2)(S2CMMe2) (CO)(2)(PPh3)(2)] (1p) and the hexasulfide [Ru-2(II)(mu-S-6)(mu-S2CNMe2)(S2CNMe2)(CO)(2)(PPh3)(2)] (Ih) complexes in the crystals of 1 . 0.5CH(2)Cl(2) were separated by partial recrystallization in benzene. The reaction between 1h and NH3 forms the dinuclear Ru-II ammine complex, {[Ru-II(S-2-CNMe2)(CO)(PPh3)(NH3)](2)(mu-S-6)} (3). 0.5CH(2)Cl(2), in which ammonia is terminally coordinated to the metal centers. Complex 3 crystallizes as the acetonitrile solvate in monoclinic space group C2/c(No. 15) with a = 30.481(7) Angstrom, b = 12.455(2) Angstrom, c = 15.463(3) Angstrom, beta = 113.90(2)degrees, V = 5367(1) Angstrom(3), and Z = 4. The reaction between 1p and excess amount of pyridine (py) yields {[Ru-II(S2CNMe2)(Co)(PPh3)(py)](2)(mu-S-5)} (4), Of which structural information was obtained by P-31 NMR and elemental analysis due to the poor crystal quality. Upon dissolution in CH2Cl2, both 3 . 0.5CH(2)Cl(2) and 4 reinstate 1h and 1p, respectively, indicating that both complexes undergo intrinsically the same reaction. The N2H4 ligand in 2 0.5CH2C12 is chemically reduced and quantitatively measured 8.4 mol % of ammonia liberation.