1129540-14-2Relevant academic research and scientific papers
Reactivity of 5-(Alkynyl)dibenzothiophenium Salts: Synthesis of Diynes, Vinyl Sulfones, and Phenanthrenes
Kafuta, Kevin,Rugen, Christian J.,Heilmann, Tobias,Liu, Tianshu,Golz, Christopher,Alcarazo, Manuel
, p. 4038 - 4048 (2021)
The reactivity of 5-(alkynyl)dibenzothiophenium salts 1 is explored in the presence of different nucleophiles, dienes, and under photochemical conditions. Reaction with lithium acetylides affords diynes in moderate yields; while depending on the substitution pattern, the reaction with sulfinates delivers either the alkyne transfer products, alkynyl sulfones, or β-(sulfonium) vinyl sulfones through addition to the C?C triple bond. Similar behavior is observed when tosylamines are used as nucleophiles. Salts of general formula 1 also react with dienes to render the corresponding Diels-Alder cycloadducts. The vinyl sulfonium salts obtained by these routes further react with nucleophiles through a Michael addition, dibenzothiophene elimination sequence. Alternatively, they also engage in photoinduced radical cyclizations to produce substituted phenanthrenes. Attempts to use this specific addition/radical cyclization sequence for the construction of the 6a,7-dehydroaporphine skeleton present in several families of alkaloids are also described.
