97462-46-9Relevant academic research and scientific papers
Cationic Polar Cycloadditions of Phenylthionium Ions with Olefines: A New Route to Thiochromans
Ishibashi, Hiroyuki,Okada, Motofumi,Sato, Kazumi,Ikeda, Masazumi,Ishiyama, Ko-ichi,Tamura, Yasumitsu
, p. 90 - 95 (2007/10/02)
Reaction of 2-chloro-N,N-dimethyl-2-(phenylthio)acetamide (1a) with styrene in the presence of stannic chloride gave 3,4-dihydro-N,N-dimethyl-4-phenyl-2H-1-benzothiopyran-2-carboxamide.The same benzothiopyran was also obtained from N,N-dimethyl-2-(phenylsulfinyl)acetamide and styrene under the Pummerer reaction conditions, but in lower yield.Similarly, α-chlorosulfides derived from ethyl 2-(phenylthio)acetate, 2-(phenylthio)acetonitrile, 1-(phenylthio)-2-propanone, and thioanisole reacted with styrene to give the corresponding 4-phenylbenzothiopyrans in variable yields.The reaction of 1a with trans-stilbene gave the expected benzothiopyran derivative, but the reaction of 1a with 1,1-diphenylethylene and phenylacetylene showed some variation of the reaction course.This cycloaddition reaction was extended to the intramolecular case.A possible mechanism for the formation of the benzothiopyran is discussed.
