The acylation of an acyl complex resulting in a labile OCO tridentate ligand

Abstract

The reaction of propionic anhydride with [fac-Ru(C(O)Et)-(CO)2(H2O)3][CF3SO3] produces a new propylidin dipropionato group, which behaves as a tridentate ligand giving the neutral complex Ru(CEt(OC(O)Et)2)(CO)2(CF3SO3).

Ethane and Ethylidene Dicarboxylates from the Ruthenium(II)-Catalyzed “Disproportionative Addition” of Carboxylic Acids to Ethene

“…Complexes 1 and 5 were prepared according to literature procedures [2,5]. Catalytic runs were performed as described in reference [2].…”

“…In addition, the intermediate that accumulates during the catalysis in acetic acid appears to have a similar nature to that of 4, with C 2 H 5 groups being substituted with CH 3 groups. Moreover, different precursors can be employed for the reaction described in Equation (1) [5] has been converted into complex 4 under the conditions of the catalytic reaction. The tridentate CC 2 H 5 (OC(O)C 2 H 5 ) 2 ligand of 5 is entirely dissociated, thus yielding the [RuL n (CO) 2 ] (2Àn)þ (L ¼ RC(O)O À , CF 3 SO 3 À ) active species which initiate the cycle described in Scheme 1.…”

“…[3] The application of such techniques to transition metals with considerable anisotropy of the g and/or hyperfine tensors, such as Cu II , Co II , V IV , Mo V , or Fe III is more complicated, since only a small fraction of the EPR spectrum of these species can be excited by the pulses. Indeed, attempts to measure Mo¥¥¥Fe separations in the Mo V /Fe III state of sulfite oxidase did not result in appreciable dipolar modulations [4] and, except for a preliminary conference report on the measurement of a Cu¥¥¥Cu separation in azurin, [5] no applications to transition metals have been reported to date. An estimate of the separation of a transition metal and a nitroxide spin label can also be obtained from relaxation measurements.…”

Ethane and Ethylidene Dicarboxylates from the Ruthenium(II)-Catalyzed “Disproportionative Addition” of Carboxylic Acids to Ethene

“…[1] The structures of such supramolecular assemblies are often elucidated by NMR spectroscopy and X-ray diffraction analysis. Indeed, attempts to measure Mo¥¥¥Fe separations in the Mo V /Fe III state of sulfite oxidase did not result in appreciable dipolar modulations [4] and, except for a preliminary conference report on the measurement of a Cu¥¥¥Cu separation in azurin, [5] no applications to transition metals have been reported to date. For paramagnetic transition metals, structural determination is further complicated by the failure of NMR methods from fast paramagnetic relaxation.…”

“…Moreover, different precursors can be employed for the reaction described in Equation (1). For instance, the recently characterized [Ru(CF 3 SO 3 ){CC 2 H 5 (OC(O)C 2 H 5 ) 2 }(CO) 2 ] (5) [5] has been converted into complex 4 under the conditions of the catalytic reaction. The tridentate CC 2 H 5 (OC(O)C 2 H 5 ) 2 ligand of 5 is entirely dissociated, thus yielding the [RuL n (CO) 2 ] (2Àn)þ (L ¼ RC(O)O À , CF 3 SO 3 À ) active species which initiate the cycle described in Scheme 1.…”