Brunner, Henri and Koellnberger, Andreas and Mehmood, Arshad and Tsuno, Takashi and Zabel, Manfred (2004) Stabilization of the labile metal configuration in halfsandwich complexes [CpRh(PN)Hal]X. JOURNAL OF ORGANOMETALLIC CHEMISTRY, 689 (24). pp. 4244-4262. ISSN 0022-328X,
Full text not available from this repository. (Request a copy)Abstract
PN ligands 3 and 4, derived from 2-diphenylphosphanylmethylpyridine 2a, were synthesized, to which in the backbone a tether to a cyclopentadiene system and for comparison an Pr-i substituent were attached. The chiral compounds were resolved by introduction of a menthoxy substituent into the 2-position of the pyridine system and/or palladium complexes with enantiomerically pure co-ligands. The tripod ligand 3b contains three different binding sites (Cp, P, N) connected by a resolved chiral carbon atom. (Sc)-configuration of this tripod ligand enforces (R-Rh)-configuration at the metal atom in the halfsandwich rhodium complex (L-Ment,S-C,R-Rh)-7b. The opposite metal configuration is inaccessible. Substitution of the chloro ligand in (L-Ment,S-C,R-Rh)-7b by halide (Br,I) or pseudohalide (N-3, CN, SCN) ligands occurs with retention of configuration to give complexes 8b-11b. However, in the reaction of (L-ment,S-C,R-Rh)-7b with PPh3 the pyridine arm of the tripod ligand in compound 13b becomes detached from the metal atom. In the Cp*Rh and CpRh compounds of the bidentate PN ligands 4a and 4b both metal configurations are accessible and in complexes 14a-17a and 14b-17b they equilibrate fast. The stereochemical assignments are corroborated by 9 X-ray analyses. (C) 2004 Elsevier B.V. All rights reserved.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | HALF-SANDWICH COMPLEXES; PIANO-STOOL COMPLEX; ENANTIOSELECTIVE CATALYSIS; ASYMMETRIC CATALYSIS; CRYSTAL-STRUCTURES; OPTICAL INDUCTION; HYDROGEN-TRANSFER; LIGANDS; CRYSTALLIZATION; EPIMERIZATION; rhodium; chirality; metal configuration; retention |
| Subjects: | 500 Science > 540 Chemistry & allied sciences |
| Divisions: | Chemistry and Pharmacy > Institut für Anorganische Chemie > Alumni or Retired Professors > Prof. Dr. Henri Brunner |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 21 Jun 2021 12:41 |
| Last Modified: | 21 Jun 2021 12:41 |
| URI: | https://pred.uni-regensburg.de/id/eprint/36942 |
Actions (login required)
 |
View Item |
