Ethylenediamine: A Highly Effective Catalyst for One-Pot Synthesis of Aryl Nitroalkenes via Henry Reaction and Dehydration

Iridium-Catalyzed and pH-Dependent Reductions of Nitroalkenes to Ketones

A highly chemoselective conversion of α,β-disubstituted nitroalkenes to ketones is developed. An acid-compatible iridium catalyst serves as the key to the conversion. At a 2500 S/C ratio, nitroalkenes were readily converted to ketones in up to 72% isolated yields. A new mechanistic mode involving the reduction of nitroalkene to nitrosoalkene and N-alkenyl hydroxylamine is proposed. This conversion is ready to amplify to a gram-scale synthesis. The pH value plays an indispensable role in controlling the chemoselectivity.

Copper(ii)-catalyzed and acid-promoted highly regioselective oxidation of tautomerizable C(sp3)–H bonds adjacent to 3,4-dihydroisoquinolines using air (O2) as a clean oxidant

A novel Cu(ii)-catalyzed and acid-promoted highly regioselective oxidation of tautomerizable C(sp3)–H bonds adjacent to 1-Bn-DHIQs was developed. This method was successfully applied in the first total synthesis of canelillinoxine.

Novel total syntheses of oxoaporphine alkaloids enabled by mild Cu-catalyzed tandem oxidation/aromatization of 1-Bn-DHIQs

Novel total syntheses of oxoaporphine alkaloids such as liriodenine, dicentrinone, cassameridine, lysicamine, oxoglaucine and O-methylmoschatoline were developed. The key step of these total syntheses is Cu-catalyzed conversion of 1-benzyl-3,4-dihydro-isoquinolines (1-Bn-DHIQs) to 1-benzoyl-isoquinolines (1-Bz-IQs) via tandem oxidation/aromatization. This novel Cu-catalyzed conversion has been studied in detail, and was successfully used for constructing the 1-Bz-IQ core.

Novel total syntheses of several oxoaporphine alkaloids were developed. The Cu-catalyzed conversion of 1-benzyl-3,4-dihydro-isoquinolines (1-Bn-DHIQs) to 1-benzoyl-isoquinolines (1-Bz-IQs) as the key step of these total syntheses has also been investigated in detail.

Ethylenediamine-functionalized magnetic Fe3O4@SiO2 nanoparticles: cooperative trifunctional catalysis for selective synthesis of nitroalkenes

The designed nanocatalyst Fe₃O₄@SiO₂–NH₂ was highly active for selective synthesis of nitroalkenes through cooperative trifunctional catalysis of primary amine, secondary amine and Si–OH groups.