Pyramidalization of a carbonyl C atom in (2S)-N-(selenoacetyl)proline methyl ester

Abstract

The title compound, C8H13NO2Se, crystallizes as a non-merohedral twin with an approximate 9:1 component ratio with two symmetry-independent molecules in the asymmetric unit. Our density-functional theory (DFT) computations indicate that the carboxy C atom is expected to be slightly pyramidal due to an n→ π interaction, wherein the lone pair (n) of the Se atom overlap with the antibonding orbital (π ) of the carbonyl group. Such pyramidalization is observed in one molecule of the title compound but not the other.