Ru(xantsil)(CO)(η6-toluene)]: Synthon for a Highly Unsaturated Ruthenium(II) Complex through Facile Dissociation of the Toluene Ligand [xantsil = (9,9-dimethylxanthene-4,5-diyl)bis(dimethylsilyl)

Abstract

The reactions of [Ru(xantsil)(CO)(η6-C6H5CH3)] [1a, xantsil = (9,9-dimethylxanthene-4,5-diyl)bis(dimethylsilyl))] with some electron-donating molecules were reported. When 1a was dissolved in benzene, benzene replaced the η6-toluene ligand easily at room temperature to give [Ru(xantsil)(CO)(η6-C6H6)] (1b). The η6-toluene ligand was also substituted by sterically less demanding two-electron donors smoothly at room temperature to afford [Ru(xantsil)(CO)L3] (L = CH3CN (2), tBuNC (3), and PMe3 (4)). The X-ray diffraction studies revealed that they take a typical octahedral geometry, in which the xantsil ligand is coordinated to the Ru(II) center in κ2(Si,Si) fashion. Reactions of 1a with sterically demanding phosphines gave [Ru(xantsil)(CO)(PR3)] (R = iPr (5) and Cy (6)). According to the X-ray diffraction study, complex 6 takes a square-pyramidal geometry, in which the xantsil ligand is bound to the Ru(II) center in κ3(Si,Si,O) fashion and one of the silyl groups occupies the apical position. The coordinativ...