Synthesis, structure, and fluxional behavior of octahedral ruthenium(II) complexes with mixed oxygen-phosphine ligands. Phosphorus-31 DNMR spectroscopic studies, line shape analysis, and determination of rearrangement barriers

Abstract

The synthesis and spectroscopic properties of ether-phosphine ruthenium(II) complexes of the type Cl[sub 2]Ru([cflx P O])[sub 2] (5a, 7a-10a) and trans-Cl[sub 2]Ru(CO)(P[approximately]O)([cflx P O]) (5b, 7b-10b) are reported. Temperature-dependent [sup 31]P NMR spectra of the fluxional complexes 1b-11b and cis-Cl[sub 2]Ru(CO)(P[approximately]O)([cflx P O]) (1c-3c) were measured and by using a modified version of DNMR5, computer-generated spectra were obtained and fitted to the experimental spectra. Graphic application of the Eyring equation to the kinetic data afforded the thermodynamic parameters [Delta]H[double dagger], [Delta]S[double dagger], and [Delta]G[double dagger]. Complex 11b with the strong basic four-membered ether-phosphine 11 crystallizes in the monoclinic space group P2[sub 1]/n, with a = 11.974(2) [Angstrom], b = 10.877(2) [Angstrom], c = 29.567(6) [Angstrom], [beta] = 96.34(3)[degrees], Z = 4, and V = 3827.2(12) [Angstrom][sup 3] (R = 0.075 and R[sub w] = 0.076). 33 refs., 4 figs., 4 tabs.