Asymmetric Intermolecular Iodinative Difunctionalization of Allylic Sulfonamides Enabled by Organosulfide Catalysis: Modular Entry to Iodinated Chiral Molecules.

Electrophilic halogenation of alkenes is a powerful transformation offering a convenient route for the construction of valuable functionalized molecules. However, as a highly important reaction in this field, catalytic asymmetric intermolecular iodinative difunctionalization remains a formidable challenge. Herein, we report that an efficient Lewis basic chiral sulfide-catalyzed approach enables this reaction. By this approach, challenging substrates such as γ,γ-disubstituted allylic sulfonamides and 1,1-disubstituted alkenes with an allylic sulfonamide unit undergo electrophilic iodinative difunctionalization to give a variety of iodine-functionalized chiral molecules in good yields with excellent enantio- and diastereoselectivities. A series of free phenols as nucleophiles are successfully incorporated into the substrates. Aside from phenols, primary and secondary alcohols, fluoride, and azide also serve as efficient nucleophiles. The obtained iodinated products are a good platform molecule, which can be easily transformed into various chiral compounds such as α-aryl ketones, chiral secondary amines, and aziridines via rearrangement or substitution. Mechanistic studies revealed that the chiral sulfide catalyst displays a superior effect on control of the reactivity of electrophilic iodine and the enantioselective construction of the chiral iodiranium ion intermediate and catalyst aggregates might be formed as a resting state in the reactions.

Enantioselective Construction of Axially Chiral Amino Sulfide Vinyl Arenes by Chiral Sulfide-Catalyzed Electrophilic Carbothiolation of Alkynes.

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.

Chiral selenide-catalyzed enantioselective synthesis of trifluoromethylthiolated 2,5-disubstituted oxazolines.

Chiral selenide-catalyzed enantioselective trifluoromethylthiolation of 1,1-disubstituted alkenes is disclosed. By this method, a variety of chiral trifluoromethylthiolated 2,5-disubstituted oxazolines were obtained in good yields with high enantioselectivities. This work not only provides a new pathway for the synthesis of chiral oxazolines, but also expands the library of chiral trifluoromethylthiolated molecules.

Chiral Selenide-Catalyzed Enantioselective Allylic Reaction and Intermolecular Difunctionalization of Alkenes: Efficient Construction of C-SCF3 Stereogenic Molecules.

New approaches for the synthesis of enantiopure trifluoromethylthiolated molecules by chiral selenide-catalyzed allylic trifluoromethylthiolation and intermolecular difunctionalization of unactivated alkenes are disclosed. In these transformations, functional groups were well tolerated, and the desired products were obtained in good yields with excellent chemo-, enantio-, and diastereoselectivities. This reaction is nicely complementary to enantioselective trifluoromethylthiolation, allylic functionalization, and intermolecular alkene difunctionalization.

The Cs2CO3-Catalyzed Reaction of 2-Oxindoles with Enones for the Preparation of Indolin-3-Ones and Their Further Transformation.

The Cs2CO3-catalyzed reaction of 2-oxindoles with enones affords 2,2-disubstituted indolin-3-ones through domino "Michael addition-oxidation-ring-cleavage-C-N coupling" process. O2 acts as the sole oxidant to accomplish the oxidative process. The indolin-3-ones can be further transformed to pyridazine, azirdine-fused 3-oxindoles, 4-quinolone derivatives easily.

[Mechanism study of action on compatible using of total alkaloids of Radix Aconiti Praeparata and total glycosides or polysaccharides of Radix Paeoniae Alba therapy on rheumatoid arthritis in rats].

OBJECTIVE: To investigate the mechanism of action on compatible using of total alkaloids of Radix Aconiti Praeparata and total glycosides or polysaccharides of Radix Paeoniae Alba therapy on rheumatoid arthritis in rats. METHOD: The rat models of rheumatoid arthritis of cold and dampness syndrome were treated with total alkaloids of Radix Aconiti Praeparata and total glycosides or polysaccharides of Radix Paeoniae Alba. Observed the contents of hypothalamic L-ENK, hypothalamic-END, plasmatic SP, serumal IgG, serumal cell factors (IL-1beta, TNF-alpha, IL-6, IL-2, IL-10) by radioimmunity method and ultrastructural change of synovial cell in electron microscope. RESULT: Total alkaloids of Radix Aconiti Praeparata and total glycosides or polysaccharides of Radix Paeoniae Alba could relieve arthrocele and arthralgia and elevate the contents of L-ENK, beta-END, IL-2 and degrade the contents of SP, IgG, IL-1beta, IL-6 and inhibit abnormal secretion accentuation of synovial cell like fiber. CONCLUSION: Total alkaloids of Radix Aconiti Praeparata and total glycosides or polysaccharides of Radix Paeoniae Alba could be used to treat rheumatoid arthritis of cold and dampness syndrome. The mechanism of action might be that the contents of center endogenous opioid peptides had increased, the synthesis and release of SP had been inhibited, the disturbance of serumal cell factor had been adjusted, and the synthesis and secretion of serum immune globulin and abnormal secretion accentuation of synovial cell had been inhibited.