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

Acta Crystallogr Sect E Struct Rep Online. 2013 Apr 30;69(Pt 5):o805-6. doi: 10.1107/S1600536813011112. Print 2013 May 1.


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