Tungsten(0) complexes of p-acids N-methylpyrazinium cations and of N-methylpyrazinium radicals. Crystal and molecular structure of (C4H4N2-Me)W(CO)3(PCy3)2(PF6), Cy = cyclohexyl
Bonding characteristics of the H2-coordinating 16 valence electron species W(CO)3(PR3)2 (R = CHMe2, cyclohexyl (Cy)) were detd. by studying stable complexes with the poorly 2 electron-donating but strongly p-accepting cationic ligand N-methylpyrazinium (mpz+). In comparison with the related complex with W(CO)5, the 1H NMR and electrochem. data suggest a strong degree of p back-donation from W(CO)3(PR3)2 to the cationic acceptor in the ground state. This view is supported by the crystal structure anal. of (mpz)W(CO)3(PCy3)2(PF6) which reveals a trans,mer configuration with a short W-N bond (210.1(10) pm). Crystal data: monoclinic, space group P21/c, a 9.079(2), b 12.859(3), c 40.981(1) \AA, b 91.19(1)°, Z = 4, R = 0.067, Rw = 0.059. Redn. to the N-methylpyrazinium radical complexes yields highly resolved ESR spectra which show the loss of 1 phosphine ligand in the case of the tricarbonyl complexes. Even the W(CO)3(PR3) fragment induces considerable spin delocalization from the pyrazinium radical ligand to the metal. on SciFinder(R)
%0 Journal Article
%1 Bruns.1993b
%A Bruns, Wolfgang
%A Hausen, Hans-Dieter
%A Kaim, Wolfgang
%A Schulz, Andreas.
%D 1993
%J Journal of Organometallic Chemistry
%K carbonyl crystal methyl methylpyrazinium phosphine phosphine;ESR phosphine;electrochem radical;pyrazinium redn structure tungsten
%N 1-2
%P 121--130
%T Tungsten(0) complexes of p-acids N-methylpyrazinium cations and of N-methylpyrazinium radicals. Crystal and molecular structure of (C4H4N2-Me)W(CO)3(PCy3)2(PF6), Cy = cyclohexyl
%V 444
%X Bonding characteristics of the H2-coordinating 16 valence electron species W(CO)3(PR3)2 (R = CHMe2, cyclohexyl (Cy)) were detd. by studying stable complexes with the poorly 2 electron-donating but strongly p-accepting cationic ligand N-methylpyrazinium (mpz+). In comparison with the related complex with W(CO)5, the 1H NMR and electrochem. data suggest a strong degree of p back-donation from W(CO)3(PR3)2 to the cationic acceptor in the ground state. This view is supported by the crystal structure anal. of (mpz)W(CO)3(PCy3)2(PF6) which reveals a trans,mer configuration with a short W-N bond (210.1(10) pm). Crystal data: monoclinic, space group P21/c, a 9.079(2), b 12.859(3), c 40.981(1) \AA, b 91.19(1)°, Z = 4, R = 0.067, Rw = 0.059. Redn. to the N-methylpyrazinium radical complexes yields highly resolved ESR spectra which show the loss of 1 phosphine ligand in the case of the tricarbonyl complexes. Even the W(CO)3(PR3) fragment induces considerable spin delocalization from the pyrazinium radical ligand to the metal. on SciFinder(R)
@article{Bruns.1993b,
abstract = {Bonding characteristics of the H2-coordinating 16 valence electron species W(CO)3(PR3)2 (R = CHMe2, cyclohexyl (Cy)) were detd. by studying stable complexes with the poorly 2 electron-donating but strongly \textgreek{p}-accepting cationic ligand N-methylpyrazinium (mpz+). In comparison with the related complex with W(CO)5, the 1H NMR and electrochem. data suggest a strong degree of \textgreek{p} back-donation from W(CO)3(PR3)2 to the cationic acceptor in the ground state. This view is supported by the crystal structure anal. of [(mpz)W(CO)3(PCy3)2](PF6) which reveals a trans,mer configuration with a short W-N bond (210.1(10) pm). Crystal data: monoclinic, space group P21/c, a 9.079(2), b 12.859(3), c 40.981(1) {\AA}, \textgreek{b} 91.19(1)°, Z = 4, R = 0.067, Rw = 0.059. Redn. to the N-methylpyrazinium radical complexes yields highly resolved ESR spectra which show the loss of 1 phosphine ligand in the case of the tricarbonyl complexes. Even the W(CO)3(PR3) fragment induces considerable spin delocalization from the pyrazinium radical ligand to the metal. [on SciFinder(R)]},
added-at = {2022-06-15T11:26:56.000+0200},
author = {Bruns, Wolfgang and Hausen, Hans-Dieter and Kaim, Wolfgang and Schulz, Andreas.},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/22ffe62e0c61210ba01f79b794a93bfae/huebleriac},
interhash = {031d8563fae95f6015ad14edd3d9cbe3},
intrahash = {2ffe62e0c61210ba01f79b794a93bfae},
journal = {Journal of Organometallic Chemistry},
keywords = {carbonyl crystal methyl methylpyrazinium phosphine phosphine;ESR phosphine;electrochem radical;pyrazinium redn structure tungsten},
number = {1-2},
pages = {121--130},
timestamp = {2022-06-15T09:26:56.000+0200},
title = {Tungsten(0) complexes of \textgreek{p}-acids N-methylpyrazinium cations and of N-methylpyrazinium radicals. Crystal and molecular structure of [(C4H4N2-Me)W(CO)3(PCy3)2](PF6), Cy = cyclohexyl},
volume = 444,
year = 1993
}