Stereoselective synthesis and characterization of monocyclic cis‐β‐lactams containing 5‐methyl‐1,3,4‐thiadiazole‐2‐thiol moiety

다국어 초록 (Multilingual Abstract)

This article describes the stereoselective synthesis of monocyclic cis‐β‐lactams. The 2‐(4‐chlorophenoxy)‐acetic acid or 2‐phenoxy‐acetic acid with a carboxylic acid activator 2‐ethoxy carbonyl DCPN generate ketene in situ, which reacts with imines derived from substituted tetralone carbaldehyde yielded monocyclic cis‐β‐lactams having 5‐methyl‐1,3,4‐thiadiazole‐2‐thiol moiety through [2+2] cyclo‐addition reaction (Staudinger reaction). All structures of cis‐β‐lactams were elucidated by a spectral technique like FT‐IR, 1H and 13C NMR spectra, HRMS, and single X‐ray crystallography. The cis configuration of the β‐lactams was determined based on coupling constant (J) value using 1H NMR for hydrogens H‐3 and H‐4 of the β‐lactams ring. This work presents the synthesis of β‐lactams more simply with high yields. The products were simply purified by crystallization technique.