Premium
3‐Alkylidene‐2‐azetidinethiones: Useful Intermediates for the Synthesis of 3‐Substituted 2‐Azetidinethiones
Author(s) -
Nieschalk Jens,
Spanka Carsten,
Schaumann Ernst
Publication year - 1996
Publication title -
liebigs annalen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 0947-3440
DOI - 10.1002/jlac.199619960122
Subject(s) - chemistry , thiophenol , deprotonation , photoisomerization , adduct , diethyl malonate , trimethylsilyl , medicinal chemistry , malonate , organic chemistry , isomerization , catalysis , ion
3‐Lithiated 2‐azetidinethiones 1 were allowed to react with carbonyl compounds to give 3‐(1‐hydroxyalkyl)‐2‐azetidinethiones 3, 4 which were converted into α,β‐unsaturated β‐thiolactams 7, 8, 10 by elimination procedures. Alternatively, the title compounds were prepared by Peterson olefination of 3‐trimethylsilyl‐2‐azetidinethiones 9 . Reactions of 7, 8, 10 with thiophenol or sodium diethyl malonate provided the Michael adducts 11 . E/Z Photoisomerization of 7, 8 by visible light was observed. On deprotonation, 7a, 8a underwent allyl rearrangement to 13 .