IF<sub>5</sub> affects the final stage of the Cl–F exchange fluorination in the synthesis of pentafluoro-λ<sup>6</sup>-sulfanyl-pyridines, pyrimidines and benzenes with electron-withdrawing substituents
A difficult chlorine–fluorine (Cl–F) exchange fluorination reaction in the final stage of the preparation of pentafluoro-λ6-sulfanyl-(hetero)arenes having electron-withdrawing substituents has now been elucidated through the use of iodinepentafluoride. A major side-reaction of C–S bond cleavage was sufficiently inhibited by the potential interaction between F and I with a halogen bonding.
The first palladium‐catalyzed direct benzylic C(sp3)−H chalcogenation with diaryl disulfides and diphenyl diselenide has been established. The coupling reaction proceeds between the thioether radical and palladiumcycle intermediate. Picolinamide serves as an excellent directing group for the C−H activation of benzylic C(sp3)−H and can be easily removed. The current protocol exhibits a relatively
A novel disulfenylation of alkenes with thiophenols and their corresponding disulfides by using air as the oxidant has been achieved. This transformation provides a facile and practical protocol for the synthesis of vicinal dithioethers under mild conditions.
Discovery of practical production processes for arylsulfur pentafluorides and their higher homologues, bis- and tris(sulfur pentafluorides): Beginning of a new era of “super-trifluoromethyl” arene chemistry and its industry
作者:Teruo Umemoto、Lloyd M Garrick、Norimichi Saito
DOI:10.3762/bjoc.8.53
日期:——
Various arylsulfur pentafluorides, ArSF(5), have long been desired in both academic and industrial areas, and ArSF(5) compounds have attracted considerable interest in many areas such as medicines, agrochemicals, and other new materials, since the highly stable SF(5) group is considered a "super-trifluoromethyl group" due to its significantly higher electronegativity and lipophilicity. This article
We report a new protocol to form pentafluorosulfanyl (hetero)arenes via chlorine-fluorine exchange of (hetero)aryl tetrafluorosulfanyl chlorides by AgBF4. The method enables access to electron-deficient SF5(hetero)arenes, which are targets that are difficult to synthesize. Two advantages of AgBF4 are its ease of handling and stability. This would be a general transformation protocol.