Mol. and crystal structures of the cyclic conjugated 8-p-electron systems 1,4-bis(trimethylgermyl)- and 1,4-bis(trimethylsilyl)-1,4-dihydropyrazine and of 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-dihydropyrazine (I) were detd. by X-ray crystallog. at low temps. Whereas the first 2 species exhibit virtually planar six-membered ring conformations and very little pyramidalization at the N centers, the sterically more crowded tetra-Me deriv. I has a pronounced boat conformation with a dihedral angle of about 140° between the ring halves. These structural results are in excellent agreement with theor. calcns. as well as spectroscopic data and illustrate the exceptional structural flexibility of the antiarom. 1,4-dihydropyrazine system. on SciFinder(R)
%0 Journal Article
%1 Hausen.1985
%A Hausen, H. D.
%A Mundt, O.
%A Kaim, W.
%D 1985
%J Journal of Organometallic Chemistry
%K antiarom conformation dihydropyrazine dihydropyrazine;crystal dihydropyrazine;mol dihydropyrazine;pyrazine flexibility germyl hydro silyl silyl;structural structure
%N 3
%P 321--337
%T The structural flexibility of the antiaromatic 1,4-dihydropyrazine system. The crystal and molecular structure of organometallic derivatives
%V 296
%X Mol. and crystal structures of the cyclic conjugated 8-p-electron systems 1,4-bis(trimethylgermyl)- and 1,4-bis(trimethylsilyl)-1,4-dihydropyrazine and of 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-dihydropyrazine (I) were detd. by X-ray crystallog. at low temps. Whereas the first 2 species exhibit virtually planar six-membered ring conformations and very little pyramidalization at the N centers, the sterically more crowded tetra-Me deriv. I has a pronounced boat conformation with a dihedral angle of about 140° between the ring halves. These structural results are in excellent agreement with theor. calcns. as well as spectroscopic data and illustrate the exceptional structural flexibility of the antiarom. 1,4-dihydropyrazine system. on SciFinder(R)
@article{Hausen.1985,
abstract = {Mol. and crystal structures of the cyclic conjugated 8-\textgreek{p}-electron systems 1,4-bis(trimethylgermyl)- and 1,4-bis(trimethylsilyl)-1,4-dihydropyrazine and of 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-dihydropyrazine (I) were detd. by X-ray crystallog. at low temps. Whereas the first 2 species exhibit virtually planar six-membered ring conformations and very little pyramidalization at the N centers, the sterically more crowded tetra-Me deriv. I has a pronounced boat conformation with a dihedral angle of about 140° between the ring halves. These structural results are in excellent agreement with theor. calcns. as well as spectroscopic data and illustrate the exceptional structural flexibility of the antiarom. 1,4-dihydropyrazine system. [on SciFinder(R)]},
added-at = {2022-06-15T11:26:56.000+0200},
author = {Hausen, H. D. and Mundt, O. and Kaim, W.},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/27f1d018496cb7a62d7a05e5949c2d03c/huebleriac},
interhash = {48aec6230d25924a54d4fa1476fa6a8c},
intrahash = {7f1d018496cb7a62d7a05e5949c2d03c},
journal = {Journal of Organometallic Chemistry},
keywords = {antiarom conformation dihydropyrazine dihydropyrazine;crystal dihydropyrazine;mol dihydropyrazine;pyrazine flexibility germyl hydro silyl silyl;structural structure},
number = 3,
pages = {321--337},
timestamp = {2022-06-15T09:26:56.000+0200},
title = {The structural flexibility of the antiaromatic 1,4-dihydropyrazine system. The crystal and molecular structure of organometallic derivatives},
volume = 296,
year = 1985
}