A heterogeneous gold(I)-catalyzed cascade annulation of aldehydes with propargylamine leading to 3-substituted 2,5-dimethylpyrazines
Sign Up to like & getrecommendations! Published in 2017 at "Journal of Organometallic Chemistry"
DOI: 10.1016/j.jorganchem.2017.07.012
Abstract: Abstract A heterogeneous gold(I)-catalyzed cascade annulation reaction of aldehydes with propargylamine was achieved in 1,2-dichloroethane at 40 °C by using an MCM-41-immobilized phosphine gold(I) complex[MCM-41-PPh 3 -AuNTf 2 ] as catalyst, yielding a variety of 3-substituted… read more here.
Keywords: cascade annulation; heterogeneous gold; gold; catalyzed cascade ... See more keywords
Preparation of 4(3H)-quinazolinones from aryldiazonium salt, nitriles and 2-aminobenzoate via a cascade annulation
Sign Up to like & getrecommendations! Published in 2019 at "Tetrahedron"
DOI: 10.1016/j.tet.2018.12.065
Abstract: Abstract One-pot synthesis of 3-aryl-4(3H)-quinazolinones has been realized through a cascade annulation. Reaction of aryldiazonium salt with a nitrile provides in situ generation of a reactive nitrilium ion, which is attacked by the amino group… read more here.
Keywords: cascade annulation; aryldiazonium salt; preparation quinazolinones;
Synthesis of 3H-1,2,4-Triazol-3-ones via NiCl2-Promoted Cascade Annulation of Hydrazonoyl Chlorides and Sodium Cyanate.
Sign Up to like & getrecommendations! Published in 2021 at "Organic letters"
DOI: 10.1021/acs.orglett.1c00568
Abstract: A nickel-promoted cascade annulation reaction for the facile synthesis of 3H-1,2,4-triazol-3-ones from readily available hydrazonoyl chlorides and sodium cyanate has been developed. The transformation occurs through a cascade nickel-promoted intermolecular nucleophilic addition-elimination process, intramolecular nucleophilic… read more here.
Keywords: hydrazonoyl chlorides; chlorides sodium; promoted cascade; triazol ones ... See more keywords
Selective Synthesis of Substituted Pyridines and Pyrimidines through Cascade Annulation of Isopropene Derivatives.
Sign Up to like & getrecommendations! Published in 2022 at "Organic letters"
DOI: 10.1021/acs.orglett.2c00124
Abstract: Diverse substituted pyridines and pyrimidines with high selectivity were obtained using a concise and efficient protocol developed herein. The reaction proceeds via metal-free cascade annulation of isopropene derivatives. Using isopropene derivatives as C3 synthons, NH4I… read more here.
Keywords: substituted pyridines; cascade annulation; annulation isopropene; isopropene derivatives ... See more keywords
A Diastereoselective Cascade Annulation Approach to Bridged Polycyclic Heterocycles Involving an Unexpected Rearrangement.
Sign Up to like & getrecommendations! Published in 2022 at "Organic letters"
DOI: 10.1021/acs.orglett.2c03629
Abstract: A diastereoselective cascade annulation between allenoates and in-situ generated isoquinoline N-oxides generating sp3-rich bridged polycyclic heterocycles is disclosed. The reaction proceeds through an unprecedented non-rearomatized rearrangement and allows access to a broad range of bridged… read more here.
Keywords: bridged polycyclic; cascade annulation; diastereoselective cascade; polycyclic heterocycles ... See more keywords
Rhodium-Catalyzed [4 + 2] Cascade Annulation to Easy Access N-Substituted Indenoisoquinolinones.
Sign Up to like & getrecommendations! Published in 2023 at "Organic letters"
DOI: 10.1021/acs.orglett.3c01032
Abstract: An efficient approach for the synthesis of N-substituted indenoisoquinolinones via rhodium(III)-catalyzed C-H bond activation/subsequent [4 + 2] cyclization starting from easily available 2-phenyloxazolines and 2-diazo-1,3-indandiones has been developed. A series of indeno[1,2-c]isoquinolinones were obtained in… read more here.
Keywords: catalyzed cascade; cascade annulation; annulation; rhodium catalyzed ... See more keywords
Synthesis of Furo[2,3-b]pyran-2-ones through Ag(I)- or Ag(I)-Au(I)-Catalyzed Cascade Annulation of Alkynols and α-Ketoesters.
Sign Up to like & getrecommendations! Published in 2018 at "Organic letters"
DOI: 10.1021/acs.orglett.7b04027
Abstract: Ag(I)- or Ag(I)-Au(I)-catalyzed cascade annulation of alkynols (5-hexyn-1-ol systems) with α-ketoesters involving a dual activation process (π and σ) has been developed for the first time. This reaction proceeds through cycloisomerization of alkynol to give… read more here.
Keywords: furo pyran; annulation; cascade annulation; annulation alkynols ... See more keywords
Direct access to substituted benzo[b]carbazoles through cascade annulation of 2-vinylbenzaldehydes with indoles.
Sign Up to like & getrecommendations! Published in 2019 at "Chemical communications"
DOI: 10.1039/c8cc10253h
Abstract: A highly efficient palladium-catalyzed cascade annulation of 2-vinylbenzaldehydes with indoles has been achieved to afford 6-(3-indolyl)benzo[b]carbazoles under mild conditions in good yield and with excellent regioselectivity. Mechanistic investigations reveal that the reaction proceeds via double… read more here.
Keywords: vinylbenzaldehydes indoles; direct access; benzo carbazoles; annulation vinylbenzaldehydes ... See more keywords
Photoredox-catalyzed cascade annulation of methyl(2-(phenylethynyl)phenyl)sulfanes and methyl(2-(phenylethynyl)phenyl)selanes with sulfonyl chlorides: synthesis of benzothiophenes and benzoselenophenes
Sign Up to like & getrecommendations! Published in 2018 at "Organic chemistry frontiers"
DOI: 10.1039/c8qo00147b
Abstract: A photoredox-catalyzed cascade annulation of methyl(2-(phenylethynyl)phenyl)sulfanes and methyl(2-(phenylethynyl)phenyl)selanes with sulfonyl chlorides was developed. A variety of benzothiophenes and benzoselenophenes were obtained in moderate to good yields at ambient temperature. read more here.
Keywords: methyl phenylethynyl; catalyzed cascade; phenylethynyl phenyl; cascade annulation ... See more keywords
Cascade annulation reaction (CAR): highly diastereoselective synthesis of pyranopyrazole scaffolds
Sign Up to like & getrecommendations! Published in 2020 at "RSC Advances"
DOI: 10.1039/d0ra03400b
Abstract: An unprecedented domino protocol for the novel synthesis of highly diverse and functionalized tetrahydro pyranopyrazole scaffolds using chalcone epoxide has been reported for the first time. This synthetic protocol generates three consecutive stereogenic centres in… read more here.
Keywords: pyranopyrazole scaffolds; synthesis; highly diastereoselective; cascade annulation ... See more keywords
Selective radical cascade (4+2) annulation with olefins towards the synthesis of chroman derivatives via organo-photoredox catalysis
Sign Up to like & getrecommendations! Published in 2022 at "Chemical Science"
DOI: 10.1039/d2sc00903j
Abstract: Due to the importance of chroman frameworks in medicinal chemistry, the development of novel synthetic methods for these structures is gaining increasing interest of chemists. Reported here is a new (4 + 2) radical annulation… read more here.
Keywords: annulation olefins; cascade annulation; annulation; radical cascade ... See more keywords