Two new polymorphs of diphenyl(4-pyridyl)methyl methacrylate

Acta Crystallogr C. 2004 Nov;60(Pt 11):o824-6. doi: 10.1107/S0108270104024217. Epub 2004 Oct 22.

Abstract

The title compound (D4PyMA), C(22)H(19)NO(2), exhibits polymorphism after crystallization by slow evaporation from a binary mixture of chloroform and hexane. Long needle-like crystals have an orthorhombic structure (space group Fdd2), with one molecule in the asymmetric unit, while small tablet-like crystals exhibit a monoclinic crystal structure (space group P2(1)/n), in which two independent but chemically identical molecules comprise the asymmetric unit. The bond lengths and angles are normal, while the torsion angles around the -C-O- bond linking the diphenyl(4-pyridyl)methyl and methacrylate groups show the flexibility of the molecule by way of packing effects. The two polymorphs both contain weak C-H...pi and C-H...O/N contacts but have different conformations.