SYNTHESIS AND FLUXIONAL BEHAVIOR OF (CYCLOPENTADIENYL) AND (PENTAMETHYLCYCLOPENTADIENYL)RUTHENIUM(II) COMPLEXES WITH HEMILABILE ETHER-PHOSPHINES - P-31 DNMR SPECTROSCOPIC STUDIES AND LINE-SHAPE ANALYSIS

A series of CpRuCl(P similar to O)(2) complexes (3a-e) (Cp* = eta(5)- C(5)Me(5)) were prepared in situ by reaction of [CpRuCl2](n) (1) with the ether-phosphine ligands Ph(2)PCH(2)-D (2a-e) (D=CH2OCH3 (a), 1,3- dioxolane-2-yl (b), 1,3-dioxane-2-yl (c), 1,3-dioxepane-2-yl (d), tetr ahydrofuran-2-yl (e)) in the presence of zinc. Treatment of 3a-e and C pRuCl(P similar to O)(2) (4b,c) with AgSbF6 and NaBPh(4), respectively , afforded cationic, monochelated ruthenium(II) complexes of the type [(eta(5)-C(5)R(5))Ru(P similar to O)(P O)](+) (5a-e: R=CH3; 6b,c: R=H) . The fluxional behaviour of 5a-e and 6c was studied by temperature de pendent P-31 NMR investigations. In the case of 5a-e computer-generate d spectra were fitted to the experimental by using DNMR5. Thermodynami c parameters Delta H-not equal , Delta S-not equal , and Delta G(not e qual) were obtained via graphic application of the Eyring equation to the kinetic data. Stirring 5c, 6c under an atmosphere of carbon monoxi de results in the formation of [(eta(5)-C(5)R(5))Ru(CO)(P similar to O )(2)][SbF6] (7c: R=CH3; 8c: R=H).