Reductive Thiolation Research Articles

Cross-Electrophile Couplings of Benzyl Sulfonium Salts with Thiosulfonates via C-S Bond Activation.

A zinc-mediated cross-electrophile coupling of benzyl sulfonium salts with thiosulfonates via C-S bond cleavage was achieved. The reductive thiolation proceeded well under transition metal-free conditions to afford the desired benzyl sulfides in good yields, exhibiting both broad substrate scope and good functionality tolerance. In addition, the reaction could be applied to the use of selenosulfonate as an effective selenylation agent and be subjected to scale-up synthesis.

Nonbasic Synthesis of Thioethers via Nickel-Catalyzed Reductive Thiolation Utilizing NBS-Like N-Thioimides as Electrophilic Sulfur Donors.

The nonbasic synthesis of unsymmetrical thioethers via nickel-catalyzed reductive thiolation between aryl(hetero) iodides and N-thioimides is illustrated. N-Bromosuccinimide (NBS)-like N-thioimides were found quite reactive toward thiolation with carbon electrophiles, and a series of structurally varied thioethers were successfully prepared under mild reaction conditions. The transformation was featured with the new application of the NBS-like reagents, good functional group tolerance, and late-stage modification of biologically active scaffolds, thus providing an expeditious and efficient platform to construct polyfunctional thioethers.

Reductive thiolation and oxidative dehydroaromatization of cyclohexanones with primary amines and sodium sulfinates to access o-sulfanylanilines

HI-promoted cascade reactions of cyclohexanones with primary amines and sodium sulfinates are described, providing an unprecedented method to access o-sulfanylanilines using cyclohexanones as an aryl source and sodium sulfinates as a sulfenylating reagent.

Paired Electrolysis Enabled Ni-Catalyzed Unconventional Cascade Reductive Thiolation Using Sulfinates.

Herein, we have reported a nickel-catalyzed cascade reductive thiolation of aryl halides with sulfinates driven by paired electrolysis. This protocol uses sulfinates as the sulfur source, and various thioethers could be synthesized under mild conditions. By mechanism exploration, we find that a cascade chemical step is allowed on the electrode interface and could alter the reaction pathway in paired electrolysis, whose findings could help the discovery of novel cascade reactions with unique reactivity.

Nickel-Catalyzed Reductive Thiolation of Unactivated Alkyl Bromides and Arenesulfonyl Cyanides.

The cross-electrophile coupling between unactivated alkyl bromides with arenesulfonyl cyanides catalyzed by Ni(acac)2 under reductive conditions to form unsymmetrical sulfides is developed. This approach for sulfide synthesis is practical, relies on available, unfunctionalized materials such as alkyl (pseudo)halides, and is scalable. This catalytic strategy provides a complementary method for the preparation of unsymmetrical alkyl-aryl sulfides under mild conditions with good functional group tolerance.

Reductive Thiolation of Organic Halides via Nickel-Catalyzed Cross-Coupling

Key words cross-coupling - reductive thiolation - nickel catalysis

Nickel-catalyzed reductive thiolation and selenylation of unactivated alkyl bromides

Chalcogen-containing compounds have received considerable attention because of their manifold applications in agrochemicals, pharmaceuticals, and material science. While many classical methods have been developed for preparing organic sulfides, most of them exploited the transition-metal-catalyzed cross-couplings of aryl halides or pseudo halides with thiols or disulfides, with harsh reaction conditions usually being required. Herein, we present a user-friendly, nickel-catalyzed reductive thiolation of unactivated primary and secondary alkyl bromides with thiosulfonates as reliable thiolation reagents, which are easily prepared and bench-stable. Furthermore, a series of selenides is also prepared in a similar fashion with selenosulfonates as selenolation reagents. This catalytic method offers a facile synthesis of a wide range of unsymmetrical alkyl-aryl or alkyl-alkyl sulfides and selenides under mild conditions with an excellent tolerance of functional groups. Likewise, the use of sensitive and stoichiometric organometallic reagents can be avoided.

Reductive Thiolation Approach to Pure Cyclobutyl Phenyl Sulfide.

Reductive Thiolation Approach to Pure Cyclobutyl Phenyl Sulfide.

Concise Synthesis of Cyclothialidine Analogues (VI) with Ring Sizes from 12 to 15: Novel Macrocyclization Protocol Involving Reductive Thiolation.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Concise Synthesis of CyclothialidineAnalogues with Ring Sizes from 12 to 15: Novel MacrocyclizationProtocol Involving Reductive Thiolation

The DNA gyrase inhibitor cyclothialidine was shown to be an interesting lead structure for the search of new antibacterials. During extensive work elucidating the structure-activity relations, it was demonstrated that variation of the lactone ring size of its bicyclic core was tolerated. Indeed, even 'seco' analogues exhibited DNA gyrase inhibitory activity. These derivatives were subsequently found to be conveniently accessible by a reductive thiolation approach. Application of this methodology to cyclic systems established an alternative, concise, and flexible synthetic access to congeners of cyclothialidine of varying ring size which so far had been prepared by Mitsunobu lactonization of the corresponding seco acids.

Preparation of symmetric bis-sulfides via reductive thiolation of dicarbonyl with thiols or of carbonyl compounds with dithiols in the presence of triethylsilane and boron trifluoride monohydrate

Symmetric organic bis-sulfides were prepared via reductive thiolation of dicarbonyl compounds with thiols or of carbonyl compounds with dithiols in the presence of triethylsilane and boron trifluoride monohydrate.

ChemInform Abstract: Reductive Thiolation of Aromatic Ketones and Benzaldehyde with Sulfur, Carbon Monoxide and Water Leading to Thiols.

AbstractReductive sulfurization of the aromatic carbonyl compounds (I) to give the corresponding thiols (II) is achieved by treatment with sulfur, carbon monoxide, and water in the presence of DBU.

一酸化炭素‐硫黄‐水系による芳香族カルボニル化合物の還元チオール化反応

The reductive thiolation of aromatic ketones and aldehyde has been investigated. Hydrogen sulfide, generated in situ from elemental sulfur, carbon monoxide, and water, reacted with various aromatic ketones and aldehyde to give the corresponding thiols in moderate to good yields.

Reactions of wood components with hydrogen sulfide. VIII. Influence of cation and base catalysts on the reductive thiolation reaction at cellulose‐reducing endgroups

AbstractIn the presence of calcium, magnesium, and ammonium ions, the reductive thiolation reaction at cellulose‐reducing endgroups by a hydrogen sulfide–hydrosulfide ion buffer system is more efficient when compared to the sodium base system. The calcium and magnesium base systems show a maximum reaction rate when the buffer pH is 5.9, thus behaving similarly to the previously described sodium base system. In the ammonium base system, however, there is a specific ammonia‐catalyzed reaction with no maximum in the reaction rate over the available pH range. The increased efficiency of the bivalent ion systems is thought to be due to the formation of a salt‐like complex between the cation and an intermediate gem‐dithiol structure in the reductive thiolation reaction scheme. Ammonia enters into the kinetics of the reaction, but the exact mechanism of its action is unclear. Some other nitrogenous bases also catalyze the reductive thiolation. The use of ammonium hydrosulfide to carry out the reductive thiolation reaction is also briefly described.

Pressure-catalytic hydrogenation of Organic Compounds by Molybdenum Sulfide Catalyst. XIII

The reaction of preparing dodecanthiol by catalytic hydrogenation (reductive thiolation reaction) of dodecanoic acid with sulfur, in cyclohexane under pressure has been investigated by using MoS3 catalyst.The reaction was proceeded above 200°c and gave dodecanthiol as the main product with a small amount of di-dodecyl disulfide as a by-product. It was advantageous to heat at about 250°c for this reaction and the amount of sulfur had great effect on the velocity of reaction. In case of 3.0 molar ratio of surfur with the reaction time of 240 min at 250°c, 90% yield of the thiol was obtained. It, was indicated from the result of similar reaction on dodecanoic anhydride and hydrogenation of thiododecanoic acid that the reducive thiolation reaction of dodecanoic acid consisted of the formation of thionic acid from reaction of H2S with dodecanoic acid and its rapid cleavage into the thiol.

Reaction of Isobutyraldehyde and 2-Ethylhexaldehyde with Ammonium Sulfide. Reductive Thiolation

Reaction of Isobutyraldehyde and 2-Ethylhexaldehyde with Ammonium Sulfide. Reductive Thiolation

The Reductive Thiolation of Fluorinated Carbonyl Compounds

The Reductive Thiolation of Fluorinated Carbonyl Compounds