Coordination ambivalence and fluxional behavior in mono- and binuclear pentacarbonyltungsten complexes of pteridine and its deaza derivatives
C. Bessenbacher, und W. Kaim. Journal of Organometallic Chemistry, 369 (1):
83--103(1989)
Zusammenfassung
WL(CO)5 (L = pteridine (pte), 1,5-naphthyridine, (npt), 1,4,5-triazanaphthalene (tan), 1,4,6-triazanaphthalene) and W2(CO)10L1 (L1 = pt, npt) were prepd. Unambiguous identification of coordination sites was only possible by use of high-resoln. 1H NMR because the chem. shifts and spin-spin coupling consts. are characteristically affected by W(CO)5-coordination to neighboring N centers. Fluxional behavior with respect to the peri coordination sites was obsd. for W(CO)5(1,4,5-tan) and W(CO)10(pte). Competition between the more basic pyridine or pyrimidine and the better p backdonating pyrazine N centers leads to various positions for the nondegenerate equil. between linkage isomers. Cyclic voltammetry and solvent-dependent charge transfer absorption spectra of the complexes reveal low-lying p* levels which can become populated after chem. or electrochem. redn., the spin distribution in the centrosym. binuclear complex of 1,5-naphthyridine anion radical was fully characterized using ESR and results from MO calcns. [on SciFinder(R)]
%0 Journal Article
%1 Bessenbacher.1989
%A Bessenbacher, Christian
%A Kaim, Wolfgang.
%D 1989
%J Journal of Organometallic Chemistry
%K carbonyl complex;triazanaphthalene complex;tungsten deaza deriv deriv;naphthyridine fluxionality pteridine tungsten
%N 1
%P 83--103
%T Coordination ambivalence and fluxional behavior in mono- and binuclear pentacarbonyltungsten complexes of pteridine and its deaza derivatives
%V 369
%X WL(CO)5 (L = pteridine (pte), 1,5-naphthyridine, (npt), 1,4,5-triazanaphthalene (tan), 1,4,6-triazanaphthalene) and W2(CO)10L1 (L1 = pt, npt) were prepd. Unambiguous identification of coordination sites was only possible by use of high-resoln. 1H NMR because the chem. shifts and spin-spin coupling consts. are characteristically affected by W(CO)5-coordination to neighboring N centers. Fluxional behavior with respect to the peri coordination sites was obsd. for W(CO)5(1,4,5-tan) and W(CO)10(pte). Competition between the more basic pyridine or pyrimidine and the better p backdonating pyrazine N centers leads to various positions for the nondegenerate equil. between linkage isomers. Cyclic voltammetry and solvent-dependent charge transfer absorption spectra of the complexes reveal low-lying p* levels which can become populated after chem. or electrochem. redn., the spin distribution in the centrosym. binuclear complex of 1,5-naphthyridine anion radical was fully characterized using ESR and results from MO calcns. [on SciFinder(R)]
@article{Bessenbacher.1989,
abstract = {WL(CO)5 (L = pteridine (pte), 1,5-naphthyridine, (npt), 1,4,5-triazanaphthalene (tan), 1,4,6-triazanaphthalene) and W2(CO)10L1 (L1 = pt, npt) were prepd. Unambiguous identification of coordination sites was only possible by use of high-resoln. 1H NMR because the chem. shifts and spin-spin coupling consts. are characteristically affected by W(CO)5-coordination to neighboring N centers. Fluxional behavior with respect to the peri coordination sites was obsd. for W(CO)5(1,4,5-tan) and W(CO)10(pte). Competition between the more basic pyridine or pyrimidine and the better \textgreek{p} backdonating pyrazine N centers leads to various positions for the nondegenerate equil. between linkage isomers. Cyclic voltammetry and solvent-dependent charge transfer absorption spectra of the complexes reveal low-lying \textgreek{p}* levels which can become populated after chem. or electrochem. redn., the spin distribution in the centrosym. binuclear complex of 1,5-naphthyridine anion radical was fully characterized using ESR and results from MO calcns. [on SciFinder(R)]},
added-at = {2022-06-15T11:26:56.000+0200},
author = {Bessenbacher, Christian and Kaim, Wolfgang.},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2248687dc2e2486673fb2c4a8d5656820/huebleriac},
interhash = {c4ede1b93002d0a9a60a50513eec5f13},
intrahash = {248687dc2e2486673fb2c4a8d5656820},
journal = {Journal of Organometallic Chemistry},
keywords = {carbonyl complex;triazanaphthalene complex;tungsten deaza deriv deriv;naphthyridine fluxionality pteridine tungsten},
number = 1,
pages = {83--103},
timestamp = {2022-06-15T09:26:56.000+0200},
title = {Coordination ambivalence and fluxional behavior in mono- and binuclear pentacarbonyltungsten complexes of pteridine and its deaza derivatives},
volume = 369,
year = 1989
}