24702-30-5

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.

A new practical procedure of imination for sulfide has been developed. The treatment of (N-tosylimino)-phenyl-λ3-iodane, PhINTs, with various sulfides in the presence of a catalytic amount of I2 under metal-free conditions affords the corresponding N-tosylsulfilimine compounds with moderate to good yields. This facile transfer procedure of the sulfonylimino group can also be applied to triphenylphosphine to produce the respective iminotriphenylphosphoranes in high yields. According to the reaction mechanism studies, the process of imination from (N-tosylimino)-phenyl-λ3-iodane to sulfide under the conditions may involve radical steps within the reaction mechanism.

Copper(I) complexes of tris(thioimidazolyl)borates (R′TmR), including [Cu(TmPh)(PR″3)] (R″ = Ph, Cu1; Cy, Cu2) and [Cu(R′TmPh)(PR″3)]+ (R′ = N-methylimidazole; R″ = Ph, Cy) were prepared an

The synthesis and characterization of new hypervalent iodine reagents ArINTs (2a), ArIO (3a), and ArIO2 (4a) (Ar=2-tert-butylsulfonyl-5- tert-butylphenyl) are described. These reagents are compared to previously reported analogous set of reagen

While excellent methods exist for the oxidation of sulfides to sulfoxides R1R2S → R1R2SO, the aza-version of this atom transfer redox process, i.e., R1R2S → R1R2S=N-SO

A number of N-sulfonylsulfilimines have been prepared through a novel way for the reaction of iodosobenzene diacetate with sulfides and sulfonamides under mild conditions.

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.

Prochiral sulfides reacted with PhI=NTs in the presence of a catalytic amount of Cu(I) salt together with a chiral 4,4′-disubstituted bis(oxazoline) ligand to afford the corresponding chiral sulfimides.

Photolysis sulfimides unexpectedly led to Stevens rearrangement products.

Prochiral sulfides react with PhI=NTs in the presence of a catalytic amount of Cu1 salt together with chiral 4,4′-disubstituted bis(oxazoline) ligands to afford the corresponding chiral sulfimides.