Zhongzhi Zhu

Copper-Catalyzed Coupling of Oxime Acetates with Isothiocyanates: A Strategy for 2-Aminothiazoles

A new strategy for 2-aminothiazoles is developed via the copper-catalyzed coupling of oxime acetates with isothiocyanates. Various 4-substituted and 4,5-disubstituted 2-aminothiazoles were formed smoothly under mild reaction conditions. This process involved copper-catalyzed N-O bond cleavage, activation of vinyl sp(2) C-H bonds, and C-S/C-N bond formations. It is noteworthy that the oxime acetates were used not only as a substrate but also as a single oxidant.

Palladium-Catalyzed Tandem Annulation: A Strategy To Construct 2,3-Difunctionalized Benzofuran Derivatives in Ionic Liquids

An efficient and ecofriendly method for the construction of 2,3-difunctionalized benzofuran derivatives in moderate to good yields from readily available 2-alkynylphenols has been developed. This tandem annulation process, featuring one pot, three steps, good functional group tolerance, and high atom economy, makes this transformation efficient and practical. Moreover, this protocol is scalable, illustrating its potential applications in synthetic and pharmaceutical chemistry.

Palladium-Catalyzed C-H Functionalization of Aromatic Oximes: A Strategy for the Synthesis of Isoquinolines.

An efficient strategy for synthesis of isoquinolines via Pd(II)-catalyzed cyclization reaction of oximes with vinyl azides or homocoupling of oximes is reported. Oximes could serve as a directing group and an internal oxidant in the transformation. This reaction features good functional group tolerance and provides a useful protocol for the synthesis of different kinds of isoquinolines under mild conditions. Some control experiments and (15)N isotope labeling experiments were conducted for the mechanistic research.

Iron-Catalyzed Synthesis of 2H-Imidazoles from Oxime Acetates and Vinyl Azides under Redox-Neutral Conditions

A novel and versatile method for the synthesis of 2H-imidazoles via iron-catalyzed [3 + 2] annulation from readily available oxime acetates with vinyl azides has been developed. This denitrogenative process involved N-O/N-N bond cleavages and two C-N bond formations to furnish 2,4-substituted 2H-imidazoles. This protocol was performed under mild reaction conditions and needed no additives or ligands. Furthermore, this is a green reaction involving oxime acetate as internal oxidant, acetic acid, and nitrogen as byproducts.

Regioselective C–H Bond Alkynylation of Carbonyl Compounds through Ir(III) Catalysis

Selective C-H bond alkynylation toward modular access to material and pharmaceutical molecules is of great desire in modern organic synthesis. Reported herein is Ir(III)-catalyzed regioselective C-H alkynylation of ketones and esters, which is generally applicable for the rapid construction of molecular complexity. This protocol provides a complementary process for conventional alkyne synthesis. Further functionalization of carbonyl-derived material molecules and pharmaceuticals demonstrates the potential synthetic utility of this methodology.

Iodine-catalyzed cascade annulation of alkynes with sodium arylsulfinates: assembly of 3-sulfenylcoumarin and 3-sulfenylquinolinone derivatives

An efficient and versatile iodine-catalyzed electrophilic cyclization has been achieved to afford functionalized 3-sulfenylcoumarin and 3-sulfenylquinolinone derivatives in moderate to good yields from readily available alkynes with sodium arylsulfinates. Moreover, broad substrate scope, excellent functional group compatibility, and high-value products make this protocol practical and attractive, offering potential applications in organic synthesis and medicinal chemistry.

Copper-Catalyzed Cyanation of N-Tosylhydrazones with Thiocyanate Salt as the “CN” Source

A novel protocol for the synthesis of α-aryl nitriles has been successfully achieved via a copper-catalyzed cyanation of N-tosylhydrazones employing thiocyanate as the source of cyanide. The features of this method include a convenient operation, readily available substrates, low-toxicity thiocyanate salts, and a broad substrate scope.

Direct Assembly of 4-Substituted Quinolines with Vinyl Azides as a Dual Synthon via C═C and C–N Bond Cleavage

An unprecedented Zn-promoted selective cleavage of vinyl azides for the synthesis of 4-substituted quinolines is developed. In this conversion, vinyl azides function as a dual synthon via C═C and C-N bond cleavage with two C═C bonds and one C═N bond formation in a one-step manner. The reaction is appreciated for its readily accessible substrates, high step economy, mild conditions, and use of air as the sole oxidant.