Binuclear radical complexes of molybdenum and tungsten tetracarbonyls with bridging N-heterocycles and Group VA ligands. ESR evidence for a cis configuration
The reactions of Mo(CO)6 or W(CO)6 and of bridging N-heterocyclic ligands (L) such as pyrazine or 4,4'-bipyridine with K were studied by ESR spectroscopy in the presence of excess phosphine, phosphite or arsine ligands. In many cases, double substitution at the metals could be obsd., yielding (XR3)(CO)4M-L-M(CO)4(XR3)-. (X = P, As; R = alkyl, aryl, alkoxy; M = Mo, W). ESR study of the complexes in THF soln. revealed extensive coupling of the unpaired electron with the nuclei 1H, 13C(CO), 14N, 31P, 75As, 95.97Mo and 183W. Evidence for a cis configuration at the metals is presented, and a p*/smx* hyperconjugation model is used to account for the facile substitution of CO and for the spin transfer to the peripheral nuclei. on SciFinder(R)
%0 Journal Article
%1 Kaim.1984c
%A Kaim, Wolfgang.
%D 1984
%J Journal of Organometallic Chemistry
%K ESR ESR;ESR ESR;phosphine arsine carbonyl dinuclear molybdenum pyrazine pyrazine;molybdenum tungsten tungsten;bipyridine tungsten;phosphite tungsten;tungsten
%N 2
%P 171--178
%R 10.1016/S0022-328X(00)99140-X
%T Binuclear radical complexes of molybdenum and tungsten tetracarbonyls with bridging N-heterocycles and Group VA ligands. ESR evidence for a cis configuration
%V 262
%X The reactions of Mo(CO)6 or W(CO)6 and of bridging N-heterocyclic ligands (L) such as pyrazine or 4,4'-bipyridine with K were studied by ESR spectroscopy in the presence of excess phosphine, phosphite or arsine ligands. In many cases, double substitution at the metals could be obsd., yielding (XR3)(CO)4M-L-M(CO)4(XR3)-. (X = P, As; R = alkyl, aryl, alkoxy; M = Mo, W). ESR study of the complexes in THF soln. revealed extensive coupling of the unpaired electron with the nuclei 1H, 13C(CO), 14N, 31P, 75As, 95.97Mo and 183W. Evidence for a cis configuration at the metals is presented, and a p*/smx* hyperconjugation model is used to account for the facile substitution of CO and for the spin transfer to the peripheral nuclei. on SciFinder(R)
@article{Kaim.1984c,
abstract = {The reactions of Mo(CO)6 or W(CO)6 and of bridging N-heterocyclic ligands (L) such as pyrazine or 4,4'-bipyridine with K were studied by ESR spectroscopy in the presence of excess phosphine, phosphite or arsine ligands. In many cases, double substitution at the metals could be obsd., yielding [(XR3)(CO)4M-L-M(CO)4(XR3)]-. (X = P, As; R = alkyl, aryl, alkoxy; M = Mo, W). ESR study of the complexes in THF soln. revealed extensive coupling of the unpaired electron with the nuclei 1H, 13C(CO), 14N, 31P, 75As, 95.97Mo and 183W. Evidence for a cis configuration at the metals is presented, and a \textgreek{p}*/\textgreek{s}mx* hyperconjugation model is used to account for the facile substitution of CO and for the spin transfer to the peripheral nuclei. [on SciFinder(R)]},
added-at = {2019-07-15T13:41:23.000+0200},
author = {Kaim, Wolfgang.},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/23ece4502651ad5ed0aa3d02cb65b467b/b_schwederski},
doi = {10.1016/S0022-328X(00)99140-X},
interhash = {83e7f7d111b4aebab2c4fafdb5c08054},
intrahash = {3ece4502651ad5ed0aa3d02cb65b467b},
journal = {Journal of Organometallic Chemistry},
keywords = {ESR ESR;ESR ESR;phosphine arsine carbonyl dinuclear molybdenum pyrazine pyrazine;molybdenum tungsten tungsten;bipyridine tungsten;phosphite tungsten;tungsten},
number = 2,
pages = {171--178},
timestamp = {2019-07-15T11:42:10.000+0200},
title = {Binuclear radical complexes of molybdenum and tungsten tetracarbonyls with bridging N-heterocycles and Group VA ligands. ESR evidence for a cis configuration},
volume = 262,
year = 1984
}