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Updated: May 10, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Pyramidalization of a carbonyl C atom in (2S)-N-(seleno-acet-yl)proline methyl ester
Ilia A Guzei1, Amit Choudhary, Ronald T Raines
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI 53706-1322, USA.
Abstract:
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.
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