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Monoclinic polymorph of 2,5-bis[4-(dimethyl-amino)-styr-yl]-3,6-dimethyl-pyrazine.

ABSTRACT: The title compound, C(26)H(30)N(4), was prepared by condensation of tetra-methyl-pyrazine and dimethyl-amino-benzaldehyde and crystallizes from chloro-form/methanol in two different forms. Block-shaped crystals belong to the monoclinic crystal system and plates to the triclinic system. The two crystal forms differ in the arrangement of the centrosymmetric mol-ecules, which have nearly identical geometries. In the monoclinic crystals reported here, planar mol-ecules [maximum deviation = 0.062?(2)?Å], with a transoid arrangement of the (E)-styryl units and completely planarized dimethylamino groups [sum of the C-N bond angles = 359.9?(2)°], form layers connected via H-?-stacking. The dihedral angle between the central and pendant rings is 1.30?(8)°. The triclinic polymorph contains two half molecules, both completed by crystallographic inversion symmetry.

SUBMITTER: Fischer J

PROVIDER: S-EPMC3099850 | biostudies-other | 2011 Apr

REPOSITORIES: biostudies-other

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Monoclinic polymorph of 2,5-bis[4-(dimethyl-amino)-styr-yl]-3,6-dimethyl-pyrazine.

Fischer Janina J Schmitt Volker V Schollmeyer Dieter D Detert Heiner H

Acta crystallographica. Section E, Structure reports online 20110312 Pt 4

The title compound, C(26)H(30)N(4), was prepared by condensation of tetra-methyl-pyrazine and dimethyl-amino-benzaldehyde and crystallizes from chloro-form/methanol in two different forms. Block-shaped crystals belong to the monoclinic crystal system and plates to the triclinic system. The two crystal forms differ in the arrangement of the centrosymmetric mol-ecules, which have nearly identical geometries. In the monoclinic crystals reported here, planar mol-ecules [maximum deviation = 0.062 (2) ...[more]

PMID: 21754152

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