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Updated: Aug 22, 2025

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
(3S,5R,6S)-Di-phenyl-methyl 1-oxo-6-bromo-penicillanate
Krishnan Soundararajan1, Velusamy Sethuraman1, Kaliyaperumal Thanigaimani2
1Department of Chemistry, Periyar Maniammai Institute of Science and Technology, Vallam-613 403, Thanjavur, Tamil Nadu, India.
Abstract:
In the title compound, C21H20BrNO4S, a key inter-mediate in the synthesis of the widely used β-lactamase inhibitor tazobactam, the five-membered thia-zolidine ring adopts an envelope conformation and the four-membered azetidine ring is in a distorted planar conformation. The crystal structure features C-H⋯O hydrogen bonds and a weak C-H⋯π inter-action.
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