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TMSOTf‐mediated 5‐endo‐dig aminocyclization followed by N‐ to C‐[1,3]‐sulfonyl migration on N‐homopropargyl hydroxylamines gave diastereoselective access to trisubstituted 3‐sulfonyl cyclic nitrone (3‐sulfonyl pyrroline N‐oxide) derivatives. The synthetic utility of the 3‐sulfonyl cyclic nitrone products was demonstrated through the diastereoselective synthesis of the sulfonyl‐substituted nonaromatic N‐heterocycles such as N‐hydroxypyrrolidine, pyrrolidine‐fused isoxazoline, and isoxazolidine derivatives. [ABSTRACT FROM AUTHOR]

The development of synthetic methods for the synthesis of organic azides is highly important, given their critical role in advancing click chemistry over the last twenty years. We report a reagent‐economical, reliable, and scalable synthesis of alkyl azides from primary and secondary alcohols. This robust click method capitalizes on the synergistic interaction between Sulfur Fluoride Exchange (SuFEx) reagents – specifically, benzene‐1,3‐disulfonyl fluoride (BDSF) or benzene‐1,3,5‐trisulfonyl fluoride (BTSF) – and trimethylsilyl azide (TMSN3). The method offers procedural ease, accommodates a wide array of substrates, and enables late‐stage functionalization. Additionally, we demonstrate the protocol's adaptability by validating a straightforward one‐pot deoxyazidation‐CuAAC sequence for drug discovery applications. [ABSTRACT FROM AUTHOR]

Designed CoNi bimetallic catalysts on various supports were synthesized and tested for selective hydrogenation reactions. Amongst these, the newly developed CoNi@gC3N4 nanocatalyst demonstrated a unique reactivity profile. It was found to be most effective for selective hydrogenation of various chalcone derivatives and nitroarenes in the presence of other reducible functional groups such as halo, carbonyl, benzyl ether, cyclopropane, and isolated alkenes. The prepared bimetallic catalyst has advantages over the reported methods in terms of catalytic activity under mild conditions, selectivity, and reusability. The catalyst CoNi@gC3N4 has ability to selectively reduce nitro functional group to amine and allows formation of quinolines. [ABSTRACT FROM AUTHOR]

The TMSOTf catalyzed intramolecular [4+2] cycloaddition of in situ generated aza‐o‐quinone methide allows an expedient, stereoselective access to cis/trans‐fused furo/pyrano[3,2‐c]tetrahydroquinolines with excellent yields and diastereoselectivity. The geometry of the dienophile olefin was found to have a profound effect on the stereochemical outcome of these reactions. [ABSTRACT FROM AUTHOR]

Synthesis and isolation of highly unstable azirinobenzoxazole and benzoxazines in a chemodivergent fashion from aryl azido vinylogous carbonates by simple change in transition metal acetate is described. Thermal or rhodium(II) acetate‐mediated decomposition of these azides gave dihydroazirino benzoxazole. Their nickel(II) acetate‐promoted reaction gave 4‐dihydro‐2H‐benzoxazines, whereas copper(II) acetate led to the corresponding oxidized imine derivatives. Benzaoxazine derivative could be kinetically resolved using a proline‐catalyzed Mannich reaction. The benzoxazines were rapidly elaborated to angularly fused tetracyclic systems and coumarin‐fused derivatives in a "one pot" fashion. Aryl azido vinylogous carbonates could be divergently converted into azirino benzoxazoles or benzoxazine derivatives by simple change in transition metal acetate and solvent. Benzaoxazine derivative could be kinetically resolved using a proline‐catalyzed Mannich reaction. "One pot" synthesis of angularly fused tetracyclic scaffold and coumarin‐fused benzoxazine derivatives is described. [ABSTRACT FROM AUTHOR]

B The Front Cover b shows bird eggs (product) with their parents (reactants). GLO:5AG/30nov20:ejoc202001247-toc-0001.jpg PHOTO (COLOR): . gl B The Front Cover b shows bird eggs (product) with their parents (reactants). These quinoline derivatives are core structures of pharmaceutically relevant chemical tools and therapeutic agents. [Extracted from the article]

Synthesis and isolation of highly unstable azirinobenzoxazole and benzoxazines in a chemodivergent fashion from aryl azido vinylogous carbonates by simple change in transition metal acetate is described. Thermal or rhodium(II) acetate-mediated decomposition of these azides gave dihydroazirino benzoxazole. Their nickel(II) acetate-promoted reaction gave 4-dihydro-2H-benzoxazines, whereas copper(II) acetate led to the corresponding oxidized imine derivatives. Benzaoxazine derivative could be kinetically resolved using a proline-catalyzed Mannich reaction. The benzoxazines were rapidly elaborated to angularly fused tetracyclic systems and coumarin-fused derivatives in a "one pot" fashion., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)