REACTION OF CP-ASTERISK-RU(NO)CL-2 WITH 2,2-DICYANO-1,1-ETHYLENEDITHIOLATE (I-MNT) - REDOX CHEMISTRY AND X-RAY-DIFFRACTION STRUCTURE OF CP-ASTERISK-RU(NO)[S2C=C(CN)(2)]

The reaction of the disodium salt of 2,2-dicyano-1,1-ethylenedithiol ( i-mnt) with the cyclopentadienyl compound CpRu(NO)Cl-2 in methanol gi ves the new piano-stool compound CpRu(NO)(i-mnt), (1), in high yield. 1 has been isolated and characterized in solution by IR and NMR (H-1 and C-13 NMR) spectroscopic methods, and the solid-state structure has been confirmed by X-ray diffraction analysis. CpRu(Nq)(i-mnt) crysta llizes, as the CH2Cl2 solvate, in the orthorhombic space group Pbcm, a = 9.8872(6) Angstrom, b = 13.5269(8) Angstrom, c = 15.0557(8) Angstro m, V = 2013.6(2) Angstrom(3), Z = 4, d(calc) = 1.621 g . cm(-3); R = 0 .0330, R(w) = 0.0353 for 1068 observed reflections with I > 3 sigma(I) . The observed Ru-N-O bond angle of 168.9(7)degrees in the X-ray struc ture of 1 confirms the near linear nature of the nitrosyl linkage. The oxidation/reduction properties of 1 have been explored by cyclic volt ammetry, which revealed the presence of a quasi-reversible one-electro n reduction (0/1(-)) and an irreversible oxidation. A comparison of th e electrochemical data for Cp()Ru(NO)(i-mnt) with the isomeric compou nd CpRu(NO)(mnt) is also presented.