Gold-catalyzed annulations of allenes with N-hydroxyanilines to form indole derivatives with benzaldehyde as a promoter
作者:Rahul Kisan Kawade、Po-Han Huang、Somnath Narayan Karad、Rai-Shung Liu
DOI:10.1039/c3ob42131g
日期:——
Gold-catalyzed syntheses of 2,3-disubstituted indole derivatives from N-hydroxyanilines and allenes are described; these reactions require benzaldehyde as an additive to generate nitrones in situ. Our control experiments indicate that nitrones and water were indispensable in the reactions whereas N-hydroxyanilines alone were inactive nucleophiles. This synthetic method is compatible with allenes and
Gold-Catalyzed <i>N</i>,<i>O</i>-Functionalizations of 6-Allenyl-1-ynes with <i>N</i>-Hydroxyanilines To Construct Benzo[<i>b</i>]-azepin-4-one Cores
作者:Antony Sekar Kulandai Raj、Balaji S. Kale、Bhanudas Dattatray Mokar、Rai-Shung Liu
DOI:10.1021/acs.orglett.7b02629
日期:2017.10.6
Gold-catalyzedreactions of 6-allen-1-ynes with N-hydroxyanilines afford thermally stable benzoazepin-4-ones in anti-selectivity; these anti-configured products are easily isomerized to their syn-isomers on a silica column. The mechanism of reactions likely involve initial nitrone/allene cycloadditions, followed by skeletal rearrangement of resulting intermediates.
Catalytic Formal [4 + 2] Cycloadditions between Unactivated Allenes and <i>N</i>-Hydroxyaniline Catalyzed by AuCl<sub>3</sub>/CuCl<sub>2</sub>/O<sub>2</sub>
作者:Jian-Ming Chen、Chin-Jung Chang、Yao-Jin Ke、Rai-Shung Liu
DOI:10.1021/jo500009x
日期:2014.5.16
AuCl3-catalyzed formal [4 + 2]-cycloadditions betweensubstituted allenes and N-hydroxyanilines are described. This reaction sequence comprises initial isomerizations of allenes to butadienes under N2 and subsequent oxidations of N-hydroxyanilines to nitrosoarenes under O2. CuCl2 (5 mol %) was added in the second step to increase the oxidation efficiency. The reactions are compatible with various 1,1-di- and
Highly diastereoselective formation of bicyclic compounds by intramolecular cycloaddition of chiral thiaalkenyl nitrones
作者:Hans Günter Aurich、Jose-Luis Ruiz Quintero
DOI:10.1016/s0040-4020(01)89668-x
日期:1994.3
Starting from chiral mercapto alcohols 5 in several reaction steps nitrones 7 were formed which underwent spontaneously intramolecular cycloaddition to give diastereomerically pure products 8. However, during the reaction course partial racemization had occurred. In contrast, nitrones 9 in which the chiral center is adjacent to the nitrogen atom afforded a mixture of the two diastereomeric cycloadducts
Diastereoselektive Synthese von α,γ-Aminoalkoholen durch intramolekulare 1,3-dipolare Cycloaddition von Nitronen mit Allylthioether-Gruppierung und anschließende reduzierende Ringöffnung
作者:Hans Günter Aurich、Klaus-Dieter Möbus
DOI:10.1016/s0040-4039(00)82182-6
日期:1988.1
The bicyclic compounds 2 and 4 are formed by intramolecular 1,3-dipolar cycloaddition of the nitrones 1 and 3, respectively. Reductive cleavage of 2a and 4a with desulfurization yields α,γ-aminoalcohols 7 and 9, respectively, as diastereomerically pure compounds.