Thietane-2-one

Wittig condensation of a thietan-2-one with stabilized phos-phoranes. ... 

An analogous procedure has been applied to the ring opening of 4-(7-fer7-butyldimethylsiloxyhept-3-enyl)thietan-2-one leading to 10-fef -butyldimethylsiloxy-3-mercapto-dec-6-enethioic acid <2003T833>. 

Dithiane formation was also observed. N-Methyl-thiophthalimide, N-methyldithiophthalimide and xanthene-9-thione similarly undergo photoaddition to diphenylketene to yield spiro-thietan-2-ones, and thioimides add to diphenyl-N-( -tolyl)keten-imine to give analogous 2-iminothietanes. A detailed examination of the photoaddition of dithioimides to alkenes has establish-... 

The proposed mechanism, which is based on the double carbonylation of styrene oxide, is shown in Scheme 6.2. The generation of an acylcobalt carbonyl complex from the reaction of cobalt tetracarbonyl anion with an alkyl halide is followed by reaction with a thiirane. This species can undergo carbonylation, the thioester function can undergo hydrolysis to reveal a sulfido nucleophile, and intramolecular cydization then produces thietan-2-one. The thietan-2-one can undergo ring cleavage and the mercapto acid results by protonahon. 

Dichlorothietans may be hydrolysed on silica gel to j8-thiolactones or the chlorine atoms may be removed without ring opening by reduction with lithium aluminium hydride. An aldol condensation of an aldehyde with thietan-2-one went in low yield. j3-Propiothiolactones (thietan-2-ones) are cleaved by MeSCl and MeCOSCl to mixed disulphides of jS-mercaptocarboxylic acid chlorides. The polymerization rates of several )3-propiothiolactones substituted with an arylsulphonamido-group have been determined. ... 

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