Ruthenium oxo complexes of macrocyclic tertiary amines. Synthesis, electrochemistry, and reactivities of ruthenium oxo complexes of meso-2,3,7,11,12-pentamethyl-3,7,11,17-tetra-azabicyclo[11.3.1]heptadeca-1(17), 13,15-triene (L1), and X-ray crystal structure of trans-[RuIVL1(O)(NCO)]ClO4

Abstract

The new complexes trans-[RuIIIL1Cl2]Cl, trans-[RuIVL1(O)(NCO)]ClO4, and trans-[RuVI-L1(O)2][ClO4] 2{L1 = meso-2,3,7,11,12-pentamethyl-3,7,11,17-tetra-azabicyclo[1 1.3.1] heptadeca-1 (17),13,15-triene} have been prepared. Their redox chemistry was studied in comparison with the related Ru-L2-oxo system (L2 = 1,4,8,11-tetramethyl-1,4,8,11 -tetra-azacyclotetradecane). At pH 1.1, the E°, of the trans-[RuVIL1(O)2]2+/trans-[Ru IVL1(O)(H2O)]2+ couple occurs at 0.76 V vs. saturated calomel electrode. The complex cation trans-[RuIVL1(O)(NCO)]+ [space group P1, a = 7.765(1), b = 10.714(1), c = 14.076(1) Å, α = 80.49(1), β = 86.03(1), γ = 88.11(1)°, Z = 2, and R = 0.034 for 3 629 observed MO-Kα, data] has been determined by X-ray crystallography. The Ru=O distance is 1.777(2) Å. The N-Me groups all lie on the same side of the macrocyclic ring. The complex trans-[RuVIL1(O)2]2+ is capable of oxidizing alcohols, styrene, and toluene at room temperature.