Metal-free Synthesis of N-Sulfonylformamidines via Skeletal Reconstruction of Sulfonyl Oximonitriles

We firstly develop an unprecedented domino reaction of sulfonyl oximonitriles with secondary amines to streamline synthesis of N-sulfonylformamidines in decent to high yields under mild reaction conditions. In addition, the...

A novel domino protocol for three-component synthesis of new dibenzo[e,g]indoles: flexible intramolecular charge transfers

Fairly high yields of 2-aryl-3-nitrodibenzo[e,g]¬¬¬¬indoles were synthesized via a hitherto unreported domino-reaction of 9,10-phenanthrenequinone, ammonium acetate and β-nitrostyrenes in one pot. This novel three-component synthetic route is efficaciously catalysed by...

An iron-catalyzed domino reaction of donor–acceptor cyclopropanes: a diastereoselective approach towards diversely functionalized pyrrolo-quinazolines

An expeditious synthetic route to access functionalized pyrrolo[2,1-b]quinazoline scaffolds has been achieved via domino ring opening cyclization (DROC) reactions of donor–acceptor (D–A) cyclopropanes and 2-amino(methyl)aniline derivatives.

Cu(OAc)2/DABCO-mediated domino reaction of vinyl malononitriles with cyclic sulfamidate imines: access to 6-hydroxyaryl-2-aminonicotinonitriles

A novel Cu(II)-salt/DABCO-mediated one-pot access to a myriad of highly-substituted biologically relevant 2-aminonicotinonitriles possessing a resourceful phenolic moiety with satisfactory yields is reported. This method involves cyclic sulfamidate imines as...

Visible Light-driven Metal-free C–H Functionalization: Access to New Bioactive Tetrahydroisoquinoline-Butenolide Hybrids via Domino Amine Oxidation/Vinylogous Mannich Reaction

An efficient metal-free visible light-driven two-step domino reaction towards new bioactive tetrahydroisoquinoline-butenolide hybrid compounds was developed for the first time. Combination of fluorescein as photosensitizer and thiourea as an additive was found to be the most effective way to promote an aerobic amine oxidation/vinylogous Mannich domino reaction sequence with yields up to 97% for a broad substrate scope. While fluorescein without thiourea additive gave product in 84% yield, it was even observed that thiourea in absence of fluorescein is also able to promote formation of product with good yield of 75%, which is explained by a potential role of thiourea as an electron-transfer mediator in light-induced amine oxidation. Both experimental and computational evidence supported the crucial role of singlet oxygen in the developed C–H functionalization reaction. In addition, in vitro studies of tetrahydroisoquinoline-butenolide hybrid compounds demonstrated their high antischistosomal and anti-cancer activities.