N‐Heterocyclic Carbene Catalyzed [4+3] Annulation of Enals and <i>o</i>‐Quinone Methides: Highly Enantioselective Synthesis of Benzo‐ε‐Lactones
Angewandte Chemie International EditionPublished 1 July 2013
Hui Lv, Wen‐Qiang Jia, Li‐Hui Sun, Song Ye
Citations290
SJR quartileQ1
SJR score5.55
SNIP2.47
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Abstract
Enantioselectivity through H bonding: An unprecedented [4+3] annulation of enals with o-quinone methides catalyzed by N-heterocyclic carbenes (NHCs) to give benzo-ε-lactones is described. High to excellent enantioselectivity was achieved by using a chiral triazolium NHC having a free OH group, which participates in a hydrogen-bonding interaction with the substrate.
Keywords
Chemistry
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Organic Letters<i>N</i>-Heterocyclic Carbene Catalyzed Transformations of 3-Halopropenals to the Equivalents of β-Acylvinyl Anions
48 Citations2010Yihua Wu, Weijun Yao +3 more
3-Halopropenals 1 can behave as an alternative equivalent of beta-acylvinyl anions (I) in the presence of N-heterocyclic carbene precursor (IPr.HCl) and DBU to afford cyclic alpha,beta-unsaturated carbonyl derivatives, butenolides 4 and pyrazolone 6, after cyclization with 2 and 5, respectively.
Angewandte Chemie International EditionBaeyer–Villiger Oxidation and Oxidative Cascade Reactions with Aqueous Hydrogen Peroxide Catalyzed by Lipophilic Li[B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>] and Ca[B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>]<sub>2</sub>
47 Citations2012Muhammet Uyanik, Daisuke Nakashima +1 more
Two lipophilic catalysts were used for Baeyer-Villiger (BV) oxidations to give lactones in high yields to selectively obtain either unsaturated carboxylic acids or hydroxylactones inhigh yields from β-silyl cyclohexanones.
Chemistry - An Asian JournalLate‐Stage Diversification of Chiral N‐Heterocyclic‐Carbene Precatalysts for Enantioselective Homoenolate Additions
43 Citations2010Pinguan Zheng, C. A. Gondo +1 more
This approach makes the preparation of chiral N-heterocyclic carbenes possible by a single-step modification of a triazolium salt, rather than the usual need for multistep organic synthesis and challenging heterocycle formation for each member of a catalyst library.
PhytochemistryLimonoids from Trichilia elegans ssp. elegans
40 Citations1997Fernanda Rodrigues Garcez, Walmir Silva Garcez +2 more
Six new limonoids, four of which possess the uncommon seco -A, B and D carbocyclic rings, have been isolated from the seeds of Trichilia elegans and are established on the basis of 1D and 2D NMR spectroscopic techniques.
European Journal of Organic ChemistryEnzymatic Baeyer–Villiger Oxidation of Benzo‐Fused Ketones: Formation of Regiocomplementary Lactones
37 Citations2009Ana Rioz‐Martínez, Gonzalo de Gonzalo +3 more
PhytochemistryMulavanins A–E: Limonoids from Munronia delavayi
35 Citations2010Bing‐Dong Lin, Huadong Chen +5 more
Limonoids, mulavanins A-E (1-5), along with four known compounds, were isolated from whole plants of Munronia delavayi and two of the compounds showed modest antifungal activity.
Tetrahedron AsymmetryChiral relay in NHC-mediated asymmetric β-lactam synthesis II; asymmetry from NHCs derived from acyclic 1,2-diamines
34 Citations2010Nicolas Duguet, Adele Donaldson +7 more
Angewandte ChemieLactonbildung durch Rh-katalysierte Öffnung von Cyclobutanonen
32 Citations2000Masahiro Murakami, Takuo Tsuruta +1 more
Journal of Natural ProductsIsolation and Structure of 14,15β-Epoxyprieurianin From the South American Tree Guarea guidona
31 Citations1982Viera Lukáčová, Judith Polonsky +3 more
ABsTmcT.-Cell growth inhibitory constituents of the French Guiana medicinal tree Guarea guidona L. Sleumer were investigated by bioassay (PS in vitro) directed isolation procedures and found to contain prieurianin and 7-oxo-gedunin.
Chinese Science BulletinEnantioselective benzoin condensation catalyzed by bifunctional N-heterocyclic carbenes
30 Citations2010Xueliang Huang, Song Ye
The intermolecular benzoin condensation catalyzed by bifunctional N-heterocyclic carbenes has been investigated, and the corresponding α-hydroxyketones were obtained with yields up to 76% and enantioselectivities up to 99% ee.
Angewandte ChemieFamily Clustering of Baeyer–Villiger Monooxygenases Based on Protein Sequence and Stereopreference
27 Citations2005Marko D. Mihovilovič, Florian Rudroff +5 more
Angewandte ChemieN‐Heterocyclic Carbene Catalysis: Enantioselective Formal [2+2] Cycloaddition of Ketenes and <i>N</i>‐Sulfinylanilines
23 Citations2011Tengyue Jian, Lin He +2 more
PhytochemistryTrichavensin, a prieurianin derivative from Trichilia havanensis
21 Citations1996Lydia Rodríguez‐Hahn, Jorge Cárdenas +1 more
Journal of Natural ProductsInsect Antifeedant Activity of Four Prieurianin-Type Limonoids
21 Citations1985Zev Lidert, David A. Taylor +1 more
TetrahedronNHC-catalyzed annulation of enals and chalcones: further explorations on the novel synthesis of 1,3,4-trisubstituted cyclopentenes
21 Citations2011Vijay Nair, Rony Rajan Paul +4 more
Helvetica Chimica ActaTirucallane Triterpenoid Saponins from <i>Munronia delavayi</i><scp>Franch</scp>
14 Citations2007Xiang‐Hai Cai, Zhi‐Zhi Du +1 more
Four new tirucallane triterpenoid saponins, named munronosides I-IV (2-5) are isolated from the EtOH extract of the whole plants of Munronia delavayi FRANCH by chromatographic methods.
Angewandte ChemieBaeyer–Villiger Oxidation and Oxidative Cascade Reactions with Aqueous Hydrogen Peroxide Catalyzed by Lipophilic Li[B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>] and Ca[B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>]<sub>2</sub>
11 Citations2012Muhammet Uyanik, Daisuke Nakashima +1 more
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