3-Thietanones with nucleophiles

The carbonyl group of 3-thietanone reacts typically with nucleophiles such as hydrazine (to give 364), 2,4-dinitrophenylhydrazine, ° tosylhydrazine, semicarbazide, and phenylmagnesium bromide.It undergoes the Wittig reaction (e.g., the formation of 365) yields vary from 14 to 74%. Sodium hydroxide cleaves the presumed 2,2-bis-trifluoromethyl-4,4-diphenyl-3-thietanone to diphenylacetic acid. ... 

Thionyl chloride reacts with 2-phenyl-3-hydroxythietan to give 3-phenylallyl chloride rather than the expected 2-phenyl-3-chlorothietan. Of the 3-chloro-thiacycloalkanes, 3-chlorothietan is the most reactive in both 5, 1 Sff2 reactions. A substantial amount of ring-opening to allyl phenyl disulphide occurs in the reaction of 3-chlorothietan with thiophenoxide ion. Attack at sulphur by the sulphur nucleophiles has also been suggested in the reaction of 3-thietanones with hydrogen sulphide ion o mercapto-ketones and their di- and tri-sulphide derivatives are the only products, with no evidence of sulphur on the ct -position being found. 

Thionyl chloride undergoes a cyclization reaction with ketones. Enoli-zation of the intermediate sulfenyl chloride, followed by the base-induced intramolecular nucleophilic displacement reaction, produces the thietanone... 

Thietanone (53) (79LA1768) and thietane (54) (72BAU505) react with sulfur-containing nucleophiles giving ring-opened products. It is thought that these reactions are initiated by nucleophilic attack by the sulfur nucleophile on the ring sulfur. 

The reaction of 3-iodopropionyl chloride with benzyltriethylammonium tetrathiomolybdate gave /3-thiolactone 77, but in rather poor yield (Equation 21) <1997T11835>. According to the authors, the poor yield resulted from the fact that 2-thietanones easily react with various nucleophilic reagents that are present in the reaction mixture and which result in cleavage of the S—C—O bond. 

---