In:
Acta Crystallographica Section B Structural Science, International Union of Crystallography (IUCr), Vol. 64, No. 1 ( 2008-02-01), p. 84-100
Abstract:
The molecular and supramolecular structures of 18 N -arylpyrazinecarboxamides, Ar NHCO(C 4 H 3 N 2 ), have been determined, including the stoichiometric monohydrate of N -(3-methoxyphenyl)pyrazinecarboxamide, and two polymorphs of N -(4-fluorophenyl)pyrazinecarboxamide having Z ′ values of 1 and 4, respectively. The aryl groups were selected to include the geometric isomers for a compact range of substituents, namely methyl, trifluoromethyl, fluoro, chloro, methoxy and nitro groups, which exhibit markedly varied electronic properties and markedly varied behaviour as hydrogen-bond donors and acceptors. However, not all isomers in each group could be structurally investigated. A small number of derivatives containing disubstituted aryl groups have also been included in this study. The crystal structures of the solvent-free carboxamides reported here exhibit a wide range of direction-specific intermolecular forces, including N—H...N, N—H...O, C—H...N and C—H...O hydrogen bonds, and π...π stacking interactions, while the structure of N -(3-methoxyphenyl)pyrazinecarboxamide monohydrate also contains O—H...N and O—H...O hydrogen bonds. The resulting supramolecular structures can be zero-, one- or two-dimensional, although no three-dimensional supramolecular aggregation has been observed. In the finite, zero-dimensional structures, pairs of molecules are linked by hydrogen bonds to form cyclic centrosymmetric dimers. The one-dimensional structures include chains formed by the π-stacking of otherwise isolated molecules, simple chains generated by either C—H...O or C—H...N hydrogen bonds, and hydrogen-bonded chains of rings. The two-dimensional structures include examples of both π-stacked hydrogen-bonded chains and hydrogen-bonded sheets.
Type of Medium:
Online Resource
ISSN:
0108-7681
DOI:
10.1107/S0108768107051804
DOI:
10.1107/S0108768107051804/bm5049sup1.cif
DOI:
10.1107/S0108768107051804/bm5049Isup2.hkl
DOI:
10.1107/S0108768107051804/bm5049IIsup3.hkl
DOI:
10.1107/S0108768107051804/bm5049IIIsup4.hkl
DOI:
10.1107/S0108768107051804/bm5049IVsup5.hkl
DOI:
10.1107/S0108768107051804/bm5049Vsup6.hkl
DOI:
10.1107/S0108768107051804/bm5049VIIsup7.hkl
DOI:
10.1107/S0108768107051804/bm5049Xasup8.hkl
DOI:
10.1107/S0108768107051804/bm5049Xbsup9.hkl
DOI:
10.1107/S0108768107051804/bm5049XIIsup10.hkl
DOI:
10.1107/S0108768107051804/bm5049XIIIsup11.hkl
DOI:
10.1107/S0108768107051804/bm5049XIVsup12.hkl
DOI:
10.1107/S0108768107051804/bm5049XVsup13.hkl
DOI:
10.1107/S0108768107051804/bm5049XVIIsup14.hkl
DOI:
10.1107/S0108768107051804/bm5049XXsup15.hkl
DOI:
10.1107/S0108768107051804/bm5049XXIsup16.hkl
DOI:
10.1107/S0108768107051804/bm5049XXIIsup17.hkl
DOI:
10.1107/S0108768107051804/bm5049XXIIIsup18.hkl
DOI:
10.1107/S0108768107051804/bm5049XXIVsup19.hkl
Language:
Unknown
Publisher:
International Union of Crystallography (IUCr)
Publication Date:
2008
detail.hit.zdb_id:
2020841-8
SSG:
13