Copper-catalysed CN/CO coupling in water: a facile access to N-coumaryl amino acids and fluorescent tyrosine & lysine labels

Ligand-free access to benzisothiazolones and benzisoselenazolones through NiFe2O4 catalyzed concomitant annulation of 2-halobenzanilides with chalcogens and their late-stage transformations

A practical non-hazardous one-pot protocol for the synthesis of benzisothiazolones and benzisoselenazolones, involving magnetically retrievable nano-nickel ferrite catalyzed tandem annulation between 2-halobenzanilides and elemental S8 or Se.

Recent Advances in Microwave-Assisted Copper-Catalyzed Cross-Coupling Reactions

Cross-coupling reactions furnishing carbon–carbon (C–C) and carbon–heteroatom (C–X) bond is one of the most challenging tasks in organic syntheses. The early developed reaction protocols by Ullmann, Ullman–Goldberg, Cadiot–Chodkiewicz, Castro–Stephens, and Corey–House, utilizing elemental copper or its salts as catalyst have, for decades, attracted and inspired scientists. However, these reactions were suffering from the range of functional groups tolerated as well as severely restricted by the harsh reaction conditions often required high temperatures (150–200 °C) for extended reaction time. Enormous efforts have been paid to develop and achieve more sustainable reaction conditions by applying the microwave irradiation. The use of controlled microwave heating dramatically reduces the time required and therefore resulting in increase in the yield as well as the efficiency of the reaction. This review is mainly focuses on the recent advances and applications of copper catalyzed cross-coupling generation of carbon–carbon and carbon–heteroatom bond under microwave technology.

Additive-Driven Rhodium-Catalyzed [4+1]/[4+2] Annulations of N-Arylphthalazine-1,4-dione with α-Diazo Carbonyl Compounds

A Rh(III)-catalyzed strategy involving the [4+1] annulation of 2-arylphthalazine-1,4-diones with α-diazo carbonyl compounds was developed, accessing a series of unprecedented hydroxy-dihydroindazolo-fused phthalazines in good to excellent yields. By varying the additive, phthalazino-fused cinnolines were synthesized under Rh-catalyzed conditions via [4+2] annulation between the same starting materials. Notably, such two strategies showed a good functional group tolerance and high atom efficiency.

Iridium-catalyzed [4 + 2] annulation of 1-arylindazolones with α-diazo carbonyl compounds: access to indazolone-fused cinnolines

An Ir-catalyzed tandem strategy for the synthesis of indazolone-fused cinnolines by [4 + 2] annulation of 1-arylindazolones with α-diazo carbonyl compounds.

An unprecedented tandem synthesis of fluorescent coumarin-fused pyrimidines via copper-catalyzed cross-dehydrogenative C(sp3)–N bond coupling

A Cu-catalyzed tandem strategy for the synthesis of coumarin-fused pyrimidin-5-ones involving in situ intramolecular cross-dehydrogenative C(sp³)–N bond formation.

Construction of β-Trifluoromethyl Enol Ether via Base-Promoted C-O Coupling and Rearrangement of Hydrogen Atom

A novel, high-efficiency and high-selectivity construction of β-trifluoromethyl enol ether via base-induced/promoted C-O coupling of trifluoromethylated vinyl chloride and phenols is presented with a broad substrate scope. The reaction mechanism, especially the significantly high selectivity, was excavated and understood via DFT calculation and is well supported by the experimental observation.