24702-35-0Relevant academic research and scientific papers
Catalytic Chemoselective Sulfimidation with an Electrophilic [CoIII(TAML)]?-Nitrene Radical Complex**
van Leest, Nicolaas P.,van der Vlugt, Jarl Ivar,de Bruin, Bas
supporting information, p. 371 - 378 (2020/12/01)
The cobalt species PPh4[CoIII(TAMLred)] is a competent and stable catalyst for the sulfimidation of (aryl)(alkyl)-substituted sulfides with iminoiodinanes, reaching turnover numbers up to 900 and turnover frequencies of 640 min?1 under mild and aerobic conditions. The sulfimidation proceeds in a highly chemoselective manner, even in the presence of alkenes or weak C?H bonds, as supported by inter- and intramolecular competition experiments. Functionalization of the sulfide substituent with various electron-donating and electron-withdrawing arenes and several alkyl, benzyl and vinyl fragments is tolerated, with up to quantitative product yields. Sulfimidation of phenyl allyl sulfide led to [2,3]-sigmatropic rearrangement of the initially formed sulfimide species to afford the corresponding N-allyl-S-phenyl-thiohydroxylamines as attractive products. Mechanistic studies suggest that the actual nitrene transfer to the sulfide proceeds via (previously characterized) electrophilic nitrene radical intermediates that afford the sulfimide products via electronically asynchronous transition states, in which SET from the sulfide to the nitrene radical complex precedes N?S bond formation in a single concerted process.
Catalytic Asymmetric Sulfimidation
Takada, Hiroya,Nishibayashi, Yoshiaki,Ohe, Kouichi,Uemura, Sakae,Baird, Charlotte P.,Sparey, Tim J.,Taylor, Paul C.
, p. 6512 - 6518 (2007/10/03)
A direct catalytic imidation of sulfides to sulfimides with [N-(p-tolylsulfonyl)imino]phenyliodinane (TsN=IPh) using a catalytic amount of copper triflate (CuOTf) has been developed. The reaction proceeds with a wide range of sulfides to give the corresponding sulfimides in 50-83% isolated yields. When the reaction is applied to allylic sulfides, the products are the corresponding sulfonamides produced via [2,3] sigmatropic rearrangement of the initially formed allylic sulfimides. In the presence of a chiral bis(oxazoline) as ligand, asymmetric induction occurs to afford the chiral sulfimides (up to 71% ee) and sulfonamides (up to 58% ee). Chloramine T (TsNClNa) can be used in place of TsN=IPh for asymmetric sulfimidation, but the ee's are much lower. Some mechanistic observations are described.
