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A mild and regioselective method for the preparation of unsymmetrical biaryl sulfides using iron(III) catalysis is described. Activation of N-(arylthio)succinimides using the powerful Lewis acid iron(III) triflimide allowed the efficient thiolation of a range of arenes, including anisoles, phenols, acetanilides, and N-heterocycles. The method was applicable for the late-stage thiolation of tyrosine and tryptophan derivatives and was used as the key step for the synthesis of pharmaceutically relevant biaryl sulfur-containing compounds such as the antibiotic dapsone and the antidepressant vortioxetine. Kinetic studies revealed that while N-(arylthio)succinimides bearing electron-deficient arenes underwent thioarylation catalyzed entirely by iron(III) triflimide, N-(arylthio)succinimides with electron-rich arenes displayed an autocatalytic mechanism promoted by the Lewis basic product.

An efficient nickel-catalyzed vicinal thiosulfonylation of 1-bromoalkynes with thiosulfonates in the presence of cesium carbonate is described. An operationally simple and highly regioselective atom transfer radical addition (ATRA) of alkynyl bromides provides a wide range of (E)-1,2-thiosulfonylethenes (α-aryl-β-thioarylvinyl sulfones) in moderate to high yields. The extensive substrate scope of both alkynyl bromides and thiosulfonates is explored with a broad range of functional groups. Indole-derived 1,1-bromoalkenes were also successfully explored in this 1,2-thiosulfonylation process. Moreover, the nickel-catalyzed geminal -dithiolation of alkynyl bromides with N -arylthio succinimides provides 1,1-dithioalkenes in high yields. The present protocol is reliable on gram scale, and a sequential one-pot bromination and thiosulfonylation of phenylacetylene is achieved in a scale-up synthesis. Following control experiments, a plausible mechanism is proposed to rationalize the experimental outcome and the vicinal thio-sulfonylation.

An efficient approach via catalytic electrophilic thiocarbocyclization of allenes to construct indene-based sulfides with excellent regioselectivities is disclosed. The reactions were carried out at low temperatures by selenide catalysis in the presence o

Thiolation/cyclization of homopropargylic tosylamides allowed the selective synthesis of 3-thiolated pyrroles and pyrrolines controlled by solvents. Moreover, the desired 3-thiolated pyrroles were readily transformed to organic fluorophores benzothienopyrrole and bisthiolated boron dipyrromethene (S-BODIPY).

The enantioselective construction of axially chiral compounds by electrophilic carbothiolation of alkynes is disclosed for the first time. This enantioselective transformation is enabled by the use of a Ts-protected bifunctional sulfide catalyst and Ms-protected ortho-alkynylaryl amines (Ts=tosyl; Ms=mesyl). Both electrophilic arylthiolating and electrophilic trifluoromethylthiolating reagents are suitable for this reaction. The obtained products of axially chiral vinyl–aryl amino sulfides can be easily converted into biaryl amino sulfides, biaryl amino sulfoxides, biaryl amines, vinyl–aryl amines, and other valuable difunctionalized compounds.

An unprecedented reactivity of (E)-β-iodovinyl sulfones in the presence of NaOAc is reported. The (E)-β-iodovinyl sulfones were treated with NaOAc in DMSO/H2O to yield β-keto sulfones in moderate to high yields. A novel oxidative difunctionalization of β-iodovinyl sulfones with thiosulfonates and NaOAc in DMF has been developed. This metal-free oxosulfenylation is an operationally simple to access a wide range of β-keto thiosulfones (α-thioaryl-β-keto sulfones) in moderate to high yields. The transformations were reliable at gram-scale, thus illustrating its efficiency and practicality. A plausible mechanism for the protocol is also proposed.

Activation of disulfides with N-halogen succinimide in the presence of TEMPO allows insertion reaction by an isocyanide, the product of which can further accept a wide range of nucleophiles for the generation of isothioureas and related molecular moieties. This new procedure overcomes previous methods that accept essentially only aryl amines as the third nucleophilic component. The diverse nucleophiles usable in our new protocol make this approach a general method for de novo synthesis of many S-containing heterocycles.

A novel and efficient method for the synthesis of N-S substituted sulfoximines has been established with h-BN-supported copper(II) nanomaterial as the catalyst. Catalyzed by this heterogeneous catalyst, the desired products were obtained with wide scope of substrates, good to excellent yields, free ligand and low-toxicity solvent. Moreover, after being reused ten times, there is almost no significant loss of its catalytic activity.

A Lewis base/Bronsted acid catalyzed aromatic sulfenylation is reported. These studies demonstrated that the incorporation of electron-rich sulfenyl groups proceeded in the absence of a Lewis base, with kinetic studies indicating an autocatalytic mechanism. The incorporation of electron-poor sulfenyl groups demonstrated little autocatalysis necessitating the use of a Lewis base. This method proved amenable to diverse arenes and heterocycles and was effective in the context of the late-stage functionalization of biologically active small molecules.

A method for the AlCl3-catalyzed intermolecular oxidative annulation of N-(arylthio)phthalimide derivatives with alkynes has been developed. The annulation reaction occurs at room temperature and involves the oxidative cleavage of the S–N bond and 1,2-sulfur migration, which leads to the construction of diverse arrays of π-conjugated 6-substituted 2,3-diarylbenzo[b]thiophene derivatives.

The Rh(ii)-catalyzed sulfur ylide [1,2]-rearrangement of carbenoids generated from aryldiazoacetates has been realized via N-S bond insertion, generating tertiary sulfides in moderate to excellent yields. This demonstrates the first use of the sulfur ylide [1,2]-rearrangement undergoing N-S bond insertion. This protocol could proceed smoothly with high regioselectivity, low catalyst loading (0.1 mol% Rh2(OAc)4), gram-scale reaction and broad substrate scope. And the product could be converted into glycine derivatives through simple procedures.

A simple and efficient metal-free sulfenylation/cyclization of aryl alkynoates has been developed, obtaining various 3-sulfenylated coumarins in moderate to excellent yields. In the presence of BF3·Et2O, the stable and readily access

A simple, efficient, and practical metal-free C-H sulfenylation of substituted electron-rich arenes has been developed. This method is highly regioselective, and the corresponding aryl sulfides were obtained in moderate to excellent yields from stable and

A simple, efficient and practical metal-free C-H sulfenylation process at the C2 position of non-protected indoles has been developed. 2-Thioindoles were obtained in moderate to high yields using stable and readily available N-(thio)succinimides at room temperature in the presence of TFA.

A general palladium-catalyzed aryl(alkyl)thiolation of various substituted unactivated arenes is accomplished for the synthesis of diverse unsymmetrical diaryl(alkyl) sulfides in good yield employing electrophilic sulfur reagent 6 derived from succinimide. The developed strategy was coupled with intramolecular arylation of a C-H bond to afford dibenzothiphene derivatives, an important moiety in material science as organic semiconductors.

(Chemical Equation Presented) Thioimides and carboxylic acids are used as the precursors for the convenient synthesis of thiolesters in the phosphine mediated process. Cyclic and acyclic thioimides show equal efficiency, furnishing the desired thiolesters in good to excellent yields. The general, highly efficient transformation tolerates various functional groups and the resulting thiolesters are obtained in high purity after a simple separation. The reaction scope has been demonstrated on the preparation of several highly functionalized target molecules.

(equation presented) A new synthesis of thioethers is described. The reaction of boronic acids with aryl, heteroaryl, and alkyl N-thioimides in the presence of catalytic quantities of a Cu(I) carboxylate affords good to excellent yields of thioethers. This reaction takes place in the absence of a base under mild conditions (THF, 45-50°C, 2.5-12 h) and represents an interesting complement to known methods for thioether synthesis.

Disulfides, sulfenyl chlorides, thiosulfonates, and sulfensuccinimides were evaluated as electrophilic thiating agents for converting the enamine 6-dehydroxynupharidine to α-thiohemiaminal derivatives of the alkaloid deoxynupharidine.Sulfensuccinimides we