Cyclopentadienyl Ligand Effects on Enthalpies of Protonation of the Ru-Ru Bond in Cp'(2)Ru(2)(CO)(4) Complexes
Nataro, C; Thomas, LM; Angelici, RJ
| HERO ID | 5435556 |
|---|---|
| In Press | No |
| Year | 1997 |
| Title | Cyclopentadienyl Ligand Effects on Enthalpies of Protonation of the Ru-Ru Bond in Cp'(2)Ru(2)(CO)(4) Complexes |
| Authors | Nataro, C; Thomas, LM; Angelici, RJ |
| Journal | Inorganic Chemistry |
| Volume | 36 |
| Issue | 26 |
| Page Numbers | 6000-6008 |
| Abstract | Basicities of a series of Cp'(2)Ru(2)(CO)(4) complexes were established by measuring the heats evolved (DeltaH(MHM)) when the complexes were protonated by CF(3)SO(3)H in 1,2-dichloroethane at 25.0 degrees C. Spectroscopic studies show that the protonation occurs at the metal-metal bond to form [Cp'(2)Ru(2)(CO)(4)(&mgr;-H)](+)CF(3)SO(3)(-), in which all of the CO ligands are terminal. The basicities (-DeltaH(MHM)) increase with the Cp'(2) ligands in the following order: (C(5)Me(4)CF(3))(2) < (C(9)H(7))(2) < C(5)H(4)C(5)H(4) < C(5)H(4)CH(2)CH(2)C(5)H(4) < (C(5)H(5))(2) < (C(5)Me(5))(2) < C(5)H(4)CH(2)C(5)H(4). This trend can be understood in part by considering that more strongly donating Cp' ligands increase the basicity of the Ru-Ru bond. Another important factor is the CO-bridging or nonbridging form of each Cp'(2)Ru(2)(CO)(4) complex. A dimer with bridging CO groups is significantly less basic than another dimer with only terminal CO groups although the donor abilities of their Cp' ligands are nearly equal. The Ru-Ru bond in Cp(2)Ru(2)(CO)(4) is substantially more basic than the Ru in the related mononuclear CpRu(CO)(2)H. Molecular structures of [Cp(2)Ru(2)(CO)(4)(&mgr;-H)](+)CF(3)SO(3)(-), [(C(5)H(4)CH(2)C(5)H(4))Ru(2)(CO)(4)(&mgr;-H)](+)CF(3)SO(3)(-), and (C(5)H(4)CH(2)CH(2)C(5)H(4))Ru(2)(CO)(4) as determined by X-ray diffraction studies are also presented. |
| Doi | 10.1021/ic970181e |
| Pmid | 11670232 |
| Wosid | WOS:000071112900005 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |