1.2- Thiazetidine 1-oxides synthesis

A novel synthesis in which diazoketones are thermolyzed with JV-sul-finylamines leads to cyclic S-oxides such as 3,4-dihydro-1,2,3-oxathiazine and 1,2-oxazetidine derivatives. A similar synthesis utilizing diazodiketones yields, via a 4 -f 2 cycloaddition, oxathiazines (165) and, via 2 -F 2 cycliza-tion, thiazetidines (166). When sulfonyldiazoketones were used, thiazetidines 167 were the only isolated products (Eq. 33). 

Four-membered ring adducts from 2n + 2n cycloaddition of keten-imines to sulfur dioxide. Isolation of l,2-thiazetidin-3-one 1-oxides. jS-Sultames. Simple method for synthesis of substituted 1,2-thia-zetidin 1,1-dioxide. ... 

The synthesis of 3-alkyl-substituted 1,2-thiazetidine 1,1-dioxides starts by transformation of the amino acids L-Val, L-Leu, L-Ile, and L-Phe into amino alcohols. These ate converted via the bromides to the corresponding thiols 161. Immediate oxidative chlorination affords either sulfonyl chloride hydrochlorides or sulfonic acids 162 which are transformed into the parent /3-sultams 163 <2004HCA90>. Similarly, L-cystine derivatives 164 have also been transformed into the parent /3-sultams 165 by oxidative chlorination followed by cyclization (Scheme 50) C1997LA1261, 2004HCA90>. 

Kano, N. Daicho, Y Kawashima, T. A potential intermediate for the aza-Corey-Chaykovsky reaction synthesis, structure, and thermolysis of a pentacoordinate 1,2-thiazetidine 1-oxide. Org. Lett. 2006, 8, 4625. 

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