Synthesis, Characterization, and Isomerization of trans- and cis-[CoCl2(1,2- or 1,3-diphosphine)2]+ and Related Complexes
- 1 February 1987
- journal article
- Published by Oxford University Press (OUP) in Bulletin of the Chemical Society of Japan
- Vol. 60 (2) , 575-581
- https://doi.org/10.1246/bcsj.60.575
Abstract
A number of new diphosphine complexes of cobalt(III), trans- and cis-[CoCl2(dmpe, dmpp, dbpe, or dpee)2]+, trans- and cis-[CoBr2(dmpe)2]+, trans- and cis-[CoCl(H2O)(dmpe)2]2+, trans-[Co(I2 or BrI)(dmpe)2]+, and [Co(CO3)(dmpp or dbpe)]+ have been prepared and characterized, where dmpe, dmpp, dbpe, and dpee denote 1,2-bis(dimethylphosphino)ethane, 1,3-bis(dimethylphosphino)propane, 1,2-bis(dibutylphosphino)ethane, and cis-1,2-bis(diphenylphosphino)ethylene, respectively. The trans isomers of the dihalogeno complexes are stable to aquation, while the cis isomers release one of the halide ions in water fairly rapidly to yield cis-[CoX(H2O)(diphosphine)2]+ which isomerizes to the trans isomer on exposure of ultraviolet light. The cis-[CoCl2(diphosphine)2]+ complexes in methanol or ethanol solution isomerize to the trans isomer, and the rates were followed spectrophotometrically in the temperature range of 39.0–65.0 °C. The rates have a first-order dependence on the complex concentration. Both the ΔH\eweq and ΔS\eweq values for the isomerization increase in the order diphosphine=dmpe<dmpp<dbpe<dpee. This order coincides with the increasing order in cone angle of phosphine ligands, and suggests that the difference in rates among the complexes comes from a steric factor. Absorption spectra of all the complexes have been recorded and the results compared with those of the corresponding ethylenediamine complexes.This publication has 19 references indexed in Scilit:
- Preparation and Properties of Cobalt(III)–1,2-Bis(dimethylphosphino)ethane (dmpe) Complexes of the [Co(L)(dmpe)2]n+ TypeBulletin of the Chemical Society of Japan, 1987
- Coordination chemistry of higher oxidation states. 20. Synthesis and cobalt-59 NMR studies of tris(diphosphine)cobalt(3+), tris(diarsine)cobalt(3+) and related complexes. Crystal structure of tris[o-phenylenebis(dimethylarsine)]cobalt(III) tetrafluoroborate-2-waterInorganic Chemistry, 1986
- Cobalt(III)-Peroxo Complexes Containing 1,2-Bis(dimethylphosphino)ethane (dmpe) or 1,3-Bis(dimethylphosphino)propane (dmpp). Molecular Structures of [Co(O2)(dmpe)2]B(C6H5)4 and [Co(O2)(dmpp)2]BF4·H2OBulletin of the Chemical Society of Japan, 1986
- Coordination chemistry of higher oxidation states. Part 15. Cobalt(III) complexes of bi- and multi-dentate phenylphosphinesInorganica Chimica Acta, 1985
- Preparation and Circular Dichroism Spectra of trans-Dichlorocobalt(III) Complexes with (2-Aminoethyl)diphenylphosphine and Related Ligands. Crystal Structures of trans(Cl,Cl), cis(P,P)-[CoCl2{NH2CH2CH2P(C6H5)2}2]·1/2[CoCl4] and -[CoCl2{NH2CH2CH2P(C4H9)(C6H5)}2]ClO4Bulletin of the Chemical Society of Japan, 1983
- Comparative study of tertiary phosphine and arsine coordination to the transition metals. Stabilization of high formal oxidation states by o-phenylene-based chelate ligandsInorganic Chemistry, 1976
- Preparation and spectroscopic properties of cobalt(III) complexes containing phosphine ligands. The electronic structural description of side-bonded dioxygenJournal of the American Chemical Society, 1976
- Préparations des Sels de Diiodobis(éthylènediamine)cobalt(III)Bulletin of the Chemical Society of Japan, 1972
- Five-coordinate cobalt(II), four- and five-coordinate nickel(II), and six-coordinate cobalt(III) complexes of the flexible diphosphine ligand 1,3-bis(dimethylphosphino)propaneInorganica Chimica Acta, 1972
- Uncommon co-ordinating agents—I: P,P,P′,P′-tetraethylethylenediphosphineJournal of Inorganic and Nuclear Chemistry, 1960