Document Type
Article
Publication Date
1-1-2009
Abstract
The crystal structure of the title compound, C13H13NO2, is a polymorph of the structure first reported by Helliwell et al. [Acta Cryst. (2006), E62, o737-o738]. It is also monoclinic (space group P2(1)/c), but with completely different cell constants. The molecular conformations of these polymorphs differ by a 180 degrees rotation of one formyl group. The present molecule is planar [maximum deviation 0.089 (2) angstrom] with the exception of the two methyl groups which lie on either side of the plane. There are strong intra- and intermolecular N-H center dot center dot center dot O hydrogen bonds. The latter link pairs of molecules across crystallographic centers of symmetry. Two aldehyde O atoms are brought close together [2.896 (4) angstrom in this arrangement but are not hydrogen bonded. In the earlier polymorph, one formyl group is rotated by 180 degrees to yield intermolecular hydrogen bonding and an infinite polymeric chain. The other formyl group is involved in the same intramolecular hydrogen bonding as has been found here.
Divisions
CHEMISTRY
Publication Title
Acta Crystallographica Section E: Structure Reports Online
Volume
65
Publisher
International Union of Crystallography
Additional Information
Department of Chemistry, Faculty of Science Building, University of Malaya, 50603 Kuala Lumpur, MALAYSIA