TRANSITION-METAL COMPLEXES WITH SULFUR LIGANDS - PART CXXVII - AZIDO,HALIDO AND NITRIDO RUTHENIUM COMPLEXES WITH SULFUR-RICH COORDINATION SPHERES

Ru(II) and Ru(III) azido complexes were synthesized as potential precu rsors for dinitrogen complexes with sulfur-dominated coordination sphe res. NEt4[Ru(N-3)(PCy3)('S-4')] (1) was obtained from the reaction of [Ru(DMSO)(PCy3)('S-4')] with NEt4N3 ('S-4'(2-) = 1.2-bis(2-mercaptophe nylthio)ethane(2-)). The oxidation of [Ru(DMSO)(PR3)('S-4')] with I-2 yielded [Ru(I)(PR3)('S-4')] (R = Cy 2a, Pr-i 2b). The iodo ligand in 2 a and 2b could be exchanged for azide and chloride yielding [Ru(N-3)(P R3)('S-4')] (R = Cy 3a, Pr-i 3b) and [Ru(Cl)(PCy3)('S-4')] (4). The az ido ligand of 1 could not be transformed int a N-2 ligand, and the rea ction of 3a with HBF4 yielded the nitrido complex [mu-N{Ru(PCy3)('S-4' )}(2)](PF6) ([5]PF6) via a labile intermediate exhibiting an IR band a t 2070 cm(-1) at -40 degrees C. The molecular structures of 2a, 4 and [5](+) as the BPh4- salt were determined by X-ray structure analysis. Crystal data of (a) 2a . C7H8: triclinic space group <P(1)over bar>; a = 1087.4(1), b = 1089.5(1), c = 1988.8(1) pm; alpha = 74.13(1), beta = 78.66(1), gamma = 61.22(1)degrees, Z = 2; (b) 4 . CH2Cl2: triclinic space group <P(1)over bar>; a = 1088.7(5), b = 1065.6(3), c = 1778.4(6 ) pm; alpha = 80.66(2), beta = 72.10(4), gamma = 67.52(3)degrees, Z = 2; (c) [5]BPh4 . 3THF: orthorhombic space group Pna2(1); a = 1972.9(6) , b = 2606.3(6), c = 1831.1(12) pm; Z = 4. The metal centers of all th ree complexes show pseudo-octahedral coordination and exhibit no anoma lies in distance and angles. The two Ru centers in [5](BPh4). 3THF are linked via a bent nitrido bridge. (C) 1998 Elsevier Science S. A.