Structure and electrochemistry of the bridging-ligand mono-substituted diruthenium compound, [Ru2(II,III)(O2CCH3)3(admpym)(Cl)(MeOH)] (Hadmpym=2-amino-4,6-dimethylpyrimidine)

The ligand substitution reaction of Ru-2(O2CCH3)(4)Cl with 2-amino-4,6-dimethylpyrimidine (Hadmpym) under gentle refluxing conditions in methanol led to the formation of a bridging-ligand mono-substituted compound, [Ru-2(O2CCH3)(3)(admpym)(Cl)(MeOH)] (1). Compound 1 crystallized in monoclinic space group P2(1)/n (no, 14) with a = 8.3074(8) Angstrom, b = 12.3722(8) Angstrom, c = 18.913(1) Angstrom, beta = 95.559(3)degrees, V = 1934.8(3) Angstrom(3), and Z = 4. Temperature dependence of the magnetic susceptibility of I revealed it to be in a spin ground state S = 3/2 arising from the electronic configuration Of sigma(2)pi(4)delta(2)(delta*pi*)(3). Compound I undergoes three metal-centered redox reactions in electrochemistry: E-1/2((ox)) = + 0.72 V (I-a/I-c < 1, DeltaE(p) = 0.17 V); E-1/2((1,red)) = - 0.65 V (I-a/I-c approximate to 1, DeltaE(p) = 0.10 V); and E-12((2,red)) = 1.80 V (I-a/I-c much less than 1, DeltaE(p) = 0.16 V). Then, the redox species produced by electrolysis were characterized by spectroscopic studies. (C) 20021 Elsevier Science B,V, All rights reserved.