The crystal and molecular structures of an “E” 5(4H)-oxazolone related to α,β-unsaturated amino acids have been determined from three-dimensional X-ray data. C16H11NO2 (1a) is monoclinic, space group C2/c, Z = 8, a = 21.568(4), b = 6.757(2), c = 17.163(3) Å, β = 94.74(5)°.
The investigation of 5(4H) oxazolones provides, by comparison with studies of analogous systems, information on the conformational flexibility of α, β-unsaturated amino acid derivatives. The main peculiarity is the presence of an accepting nitrogen atom instead of an NH group. This allows in principle fully planar conformations, at least to monosubstituted (both “Z” and “E”) systems.
Zeitschrift für Kristallographie – Crystalline Materials offers a place for researchers to present results of their crystallographic studies. The journal includes theoretical as well as experimental research. It publishes Original Papers, Letters and Review Articles in manifold areas of crystallography.