Journal ArticleDOI
N-Heterocyclic Carbene-Catalyzed [2+2+2] Annulation of Allenoates with Trifluoromethylketones
Lihui Sun,Tong Wang,Song Ye +2 more
TLDR
In this paper, the annulation of allenoates and two molecules of trifluoromethylketone was found under the condition of N-heterocyclic carbene catalysis.Abstract:
In contrast with the reported phosphine- and DABCO-catalyzed [3+2] and [2+2] annulation of allenoates with trifluoromethylketone, the [2+2+2] annulation of allenoates and two molecules of trifluoromethylketone was found under the condition of N-heterocyclic carbene catalysis.read more
Citations
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Journal ArticleDOI
N-heterocyclic carbene-catalyzed reactions of C–C unsaturated bonds
Xiang-Yu Chen,Song Ye +1 more
TL;DR: This work has demonstrated that NHC-catalyzed reactions of C-C unsaturated bonds are feasible, including the umpolung of Michael acceptors, the Morita-Baylis-Hillman reaction, and the annulation reactions of vinyl sulfones, nitroalkenes, allenoates and alkynes.
Journal ArticleDOI
Highly enantioselective [4 + 2] cyclization of chloroaldehydes and 1-azadienes catalyzed by N-heterocyclic carbenes
Tengyue Jian,Li-Hui Sun,Song Ye +2 more
TL;DR: Highly functionalized dihydropyridinones were synthesized via the N-heterocyclic carbene-catalyzed enantioselective [4 + 2] annulation of α-chloroaldehydes and azadienes with high enantiopurity.
Journal ArticleDOI
Asymmetric, Three-Component, One-Pot Synthesis of Spiropyrazolones and 2,5-Chromenediones from Aldol Condensation/NHC-Catalyzed Annulation Reactions
Lei Wang,Sun Li,Pankaj Chauhan,Daniel Hack,Arne R. Philipps,Rakesh Puttreddy,Kari Rissanen,Gerhard Raabe,Dieter Enders +8 more
TL;DR: A novel one-pot, three-component diastereo- and enantioselective synthesis of spiropyrazolones has been developed involving the aldol condensation of an enal to generate α,β-unsaturated pyrazolons, which react with a second equivalent of enal through an N-heterocyclic carbene (NHC) annulation.
Journal ArticleDOI
Catalytic Asymmetric Synthesis of 2‐Alkyleneoxetanes through [2+2] Annulation of Allenoates with Trifluoromethyl Ketones
TL;DR: The first β-isocupreidine (β-ICD)-catalyzed highly enantioselective [2+2]-annulation of allenoates with trifluoromethyl ketones has been disclosed, allowing the synthesis of optically active 2-alkyleneoxetanes in moderate to good yields along with good to high enanti-lectivities and high diastereoselectivities as discussed by the authors.
Journal ArticleDOI
Synthesis of Trifluoromethyl Ketones via Tandem Claisen Condensation and Retro-Claisen C–C Bond-Cleavage Reaction
TL;DR: A highly efficient, operationally simple approach to trifluoromethyl ketones has been developed that builds on the use of a tandem process involving Claisen condensation and retro-Claisen C-C bond cleavage reaction.
References
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Journal ArticleDOI
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TL;DR: This study illuminates the unusual phenomena and shows how understanding of the central problem to generate a 1,3-dipole from alkynoates or allenoates by interaction with various phosphines allows control of the reaction.
Related Papers (5)
Catalytic Asymmetric Synthesis of 2‐Alkyleneoxetanes through [2+2] Annulation of Allenoates with Trifluoromethyl Ketones
Phosphine-catalyzed [3 + 2] cycloaddition of allenoates with trifluoromethylketones: synthesis of dihydrofurans and tetrahydrofurans
Tong Wang,Song Ye +1 more