SYNTHESIS, CHARACTERIZATION, AND REACTIVITY OF RUTHENIUM CARBONYL-COMPLEXES CONTAINING A CHELATING TRIPHOSPHINE LIGAND AND 2 WEAKLY COORDINATED ANIONS

Protonation of cis-mer-RuH2(CO)(Cyttp) (Cyttp = PhP(CH2CH2CH2PCy2)2) with excess HX (X = BF4, O3SCF3) in benzene/diethyl ether produces air-stable complexes with two weakly coordinated anions, viz., cis-mer-RuX2(CO)(Cyttp) (X = BF4 (2), O3SCF3 (3)). A single-crystal X-ray diffraction analysis at 223 K shows that 3 crystallizes in the space group P2(1)/c with cell parameters a = 11.712 (2) angstrom, b = 15.338 (2) angstrom, c = 27.072 (3) angstrom, beta = 98.58 (1)-degrees, Z = 4, V = 4809 (1) angstrom3, R = 0.041, and R(w) = 0.046 for the 7036 intensities with F(o)2 > 3-sigma(F(o)2) and the 539 variables. The molecules contain two cis-oriented monodentate O3SCF3- ligands. The structural behavior of 2 and 3 in both CD2Cl2 and acetone-d6 was investigated by variable-temperature P-31{H-1} and F-19{H-1} NMR spectroscopies in the range 178-303 K; a complex behavior involving species with coordinated and free BF4- and O3SCF3- ions was observed. 2 and 3 are useful synthons for a variety of coordination and organometallic complexes. 2 undergoes substitution reactions with acetonitrile and organic isocyanides to afford disubstituted complexes cis-mer-[Ru(CO)L2(Cyttp)][BF4]2 (L = MeCN, CNBu-t, CNCy). New Ru-F complexes [Ru(F)(CO)(L)(Cyttp)][BF4] (L = H2O, CO, CNBu-t) have also been synthesized from 2. The absence of fluoride abstraction from triflate and the solubility of 3 in THF render this a more versatile starting material than 2. Substitution reactions with acetonitrile and ammonia produce disubstituted complexes cis-mer- [Ru(CO)L2(Cyttp)][O3SCF3]2 (L = MeCN, NH3). The reaction of 3 with an excess of trimethyl phosphite leads only to the monosubstituted phosphite products [Ru(CO)(P(OMe)3)(Cyttp)][O3SCF3]2 (11a, 11b), which probably differ by the orientation of the Ph group of Cyttp. Complexes with the cations [Ru(X)(CO)(P(OMe)3)(Cyttp)]+ (X = Cl, OMe) are generated from reactions of mixtures of 11a and 11b with the appropriate anion. 3 also reacts with selected anions (X- = Me-, I-, and H-) to afford complexes cis-mer-RuX2(CO)(Cyttp).