Binhui Chen

One-pot three-component approach to the synthesis of polyfunctional pyrazoles.

A simple, multicomponent, and straightforward reaction of vinyl azide, aldehyde, and tosylhydrazine affords the construction of 3,4,5-trisubstituted 1H-pyrazoles regioselectively in the presence of base with moderate to excellent yields. A range of functionality could be tolerated in this methodology, and a possible mechanism is proposed.

Selective Access to 4-Substituted 2-Aminothiazoles and 4-Substituted 5-Thiocyano-2-aminothiazoles from Vinyl Azides and Potassium Thiocyanate Switched by Palladium and Iron Catalysts.

A highly selective construction of 4-substituted 2-aminothiazoles and 4-substituted 5-thiocyano-2-aminothiazoles, respectively, catalyzed by palladium(II) acetate and promoted by iron(III) bromide from vinyl azides and potassium thiocyanate has been developed. Use of readily available starting materials, high selectivity, as well as mild reaction conditions make this practical method particularly attractive.

One-Pot Three-Component Strategy for Functionalized 2-Aminoimidazoles via Ring Opening of α-Nitro Epoxides

Functionalized 2-aminoimidazole derivatives have been synthesized via a three-component domino reaction of α-nitroepoxides and cyanamide with a series of amines under mild conditions without the need for any additives. This reaction represents a practical process for the facile conversion of α-nitroepoxides to 2-aminoimidazoles via ring opening of epoxides.

Facile preparation of 3,5-disubstituted-4-aminothiophene-2-carbaldehyde from a novel unexpected domino reaction of vinyl azides and 1,4-dithiane-2,5-diol

A simple and direct synthesis of 3,5-disubstituted-4-aminothiophene-2-carbaldehyde from vinyl azides and 1,4-dithiane-2,5-diol was developed. An attractive feature of this protocol is that the desired products are generated in a highly efficient and eco-friendly manner. A plausible mechanism has been proposed.

KI-mediated radical multi-functionalization of vinyl azides: a one-pot and efficient approach to β-keto sulfones and α-halo-β-keto sulfones

Transition metal-free oxidative coupling of vinyl azides with sulfonyl hydrazines is described. This radical process realized oxidative multi-functionalization of vinyl azides in the presence of potassium iodide and t-butyl hydroperoxide, selectively yielding β-keto sulfones and α-halo-β-keto sulfones in good to excellent yields with a wide tolerance of functional groups.

Highly efficient and eco-friendly protocol to functionalized imidazoles via ring-opening of α-nitro epoxides

A simple and direct synthesis of functionalized imidazoles from α-nitro-epoxides and amidines was developed. This reaction could proceed smoothly in a highly efficient and eco-friendly manner in moderate to excellent yields. A plausible mechanism has also been proposed.

Synthesis of polysubstituted 4-aminopyrazoles and 4-hydroxypyrazoles from vinyl azides and hydrazines

A simple and direct synthesis of polysubstituted 4-aminopyrazoles and 4-hydroxypyrazoles from vinyl azides and hydrazines was developed. The present reactions were performed under mild conditions in moderate to excellent yields. A possible mechanism is also proposed.

Base-mediated synthesis of highly functionalized 2-aminonicotinonitriles from α-keto vinyl azides and α,α-dicyanoalkenes

A novel access to highly functionalized 2-aminonicotinonitriles via efficient annulations of α-keto vinyl azides and α,α-dicyanoalkenes is described. This annulation was achieved via base-mediated ring-openings and intramolecular rearrangements. A possible mechanism is also proposed.

Palladium-Catalyzed H/D Exchange Reaction with 8-Aminoquinoline as the Directing Group: Access to ortho-Selective Deuterated Aromatic Acids and β-Selective Deuterated Aliphatic Acids

We develop a palladium-catalyzed H/D exchange reaction with 8-aminoquinoline as the directing group as well as D2O as the source of deuterium atom and solvent. This reaction achieves selectively H/D exchange at the ortho-C-H of aromatic amides and the β-C-H of aliphatic amide. Ortho-deuterated aromatic acids and β-deuterated aliphatic acids are obtained by removal of the directing group. And a possible mechanism is also proposed.