I&EC 116 |
| Alan S. Goldman, Margaret Czerw, Kenton B. Renkema, Patrick D. Achord, Keming Zhu, and Karsten Krogh-Jespersen. Department of Chemistry, Rutgers University, Piscataway, NJ 08854-8087 |
| Iridium pincer complexes (PCP)IrH2 (PCP=[h3-2,6-(PR2)C6H3]) have been reported to catalyze the dehydrogenation of alkanes with high efficiency and selectivity. In overlapping studies we are developing improved catalysts, beginning with derivatization of the PCP ligand, and we have elucidated full free-energy profiles of the catalyses. For example, the derivatized catalyst (p-MeO-PCP)IrH2 is more effective than the parent. Theoretical and experimental studies have revealed the effect of varying the PCP aryl para-substituent upon the thermodynamics of small molecule (H2, arene, alkane, and CO) addition to several (PCP)Ir complexes including the parent three-coordinate (PCP)Ir as well as addition to (PCP)IrH2 and (PCP)Ir(CO). A phosphinito catalyst, (pincer ligand=[h3-2,6-(R2PO)C6H3]), has recently been reported by Brookhart; it has been computationally (DFT) demonstrated that the high activity of this complex is primarily attributable to pi-electron-donation by the O atoms to the aryl ring, rather than the inductive electron-withdrawal from the PR2 groups. |
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Advances in Catalysis of the Selective Oxidation of Hydrocarbons: E. V. Murphree Award in Industrial and Engineering Chemistry Symposium in Honor of James E. Lyons
1:30 PM-5:20 PM, Tuesday, March 30, 2004 Marriott -- Grand Ballroom F, Oral
Division of Industrial and Engineering Chemistry |