Treatment of a series of alpha-thioamides with N-chlorosuccinimide results in efficient transformation to the analogous alpha-thio-beta-chloroacrylamides. The mechanistic pathway has been established through isolation and characterisation of intermediate compounds. The scope of the transformation has been explored-aryl and alkylthio substituents, primary, secondary and tertiary amides can be employed. In most instances, the chloroacrylamides are formed exclusively as the Z-stereoisomer; however, with tertiary propanamides or with amides derived from butanoic or pentanoic acid a mixture of E- and Z-stereoisomers is formed.

No abstract

Thioethers Q 0580Investigation of the Synthetic and Mechanistic Aspects of the Highly Stereoselective Transformation of α-Thioamides to α-Thio-β-chloroacrylamides. -In the case of β-substituted amides (X) and (XIV), formation of product mixtures is also observed. Several side products are formed in low amounts, e.g. overchlorination products like (XIII) or dechlorination products like (VIII) or (XV). -(MURPHY, M.; LYNCH, D.; SCHAEFFER, M.; KISSANE, M.; CHOPRA, J.; O'BRIEN, E.; FORD, A.; FERGUSON, G.; MAQUIRE*, A. R.; Org. Biomol. Chem. 5 (2007) 8, p1228-p1241; Dep. Chem. Anal. Biol. Chem., Res. Facil., Univ. Coll. Cork, Cork, Ire.; Eng.) -Mischke 33-082

Thioethers Q 0580Investigation of the Synthetic and Mechanistic Aspects of the Highly Stereoselective Transformation of α-Thioamides to α-Thio-β-chloroacrylamides. -A wide variety of α-thioamides undergoes successful halogenation-elimination in the presence of NCS to afford the corresponding α-thio-β-chloro-acrylamides in good yields. In most cases, the reaction proceeds with excellent (Z)-selectivity. However, a mixture of E/Z isomers is obtained from tertiary amides (III) (to be continued). -(MURPHY, M.; LYNCH, D.; SCHAEFFER, M.; KISSANE, M.; CHOPRA, J.; O'BRIEN, E.; FORD, A.; FERGUSON, G.; MAQUIRE*, A. R.; Org. Biomol. Chem. 5 (2007) 8, 1228-1241; Dep. Chem. Anal. Biol. Chem., Res. Facil., Univ. Coll. Cork, Cork, Ire.; Eng.) -Mischke 33-081

No abstract