One-pot Preparation of 2,6-Disubstituted 4-(Trifluoromethyl)pyrimidines <i>via</i> the Tandem Cyclization, Dehydration, and Oxidation Reaction of α,β-Unsaturated Trifluoromethyl Ketones Using POCl<sub>3</sub>-Pyridine-Silica Gel and MnO<sub>2</sub> Systems
The treatment of α,β-unsaturated trifluoromethyl ketones with amidines in acetonitrile gave the corresponding 4-hydroxy-4-(trifluoromethyl)-3,5,6-trihydropyrimidines, followed by successive dehydration with phosphorus oxychloride-pyridine-silica gel and oxidation with manganese(IV) oxide, producing 2,6-disubstituted 4-(trifluoromethyl)pyrimidines in good to excellent yields.
Reactions of CF3-Haloenones with 1,3-Dicarbonyl Compounds: Chemo- and Stereoselective Assembly of Fluorinated Dihydrofurans
作者:Alexander V. Popov、Alexander V. Mareev、Valentina A. Kobelevskaya、Sergei V. Zinchenko、Alexander V. Vashchenko、Alexander Yu. Rulev
DOI:10.1016/j.jfluchem.2021.109819
日期:2021.8
3-diketones and β-keto esters). The reaction was generally found to proceed in moderate to good yield and excellent selectivity. The mechanism of the assembly of these heterocycles is discussed in terms of multi-step processes involving formation of Michael adduct followed by cyclization through the classical intramolecular halogen nucleophilic substitution at sp3carbon atom.
An enantioselective nucleophilic addition of α,β-unsaturated trifluoromethylketones catalyzed by l-proline derivatives
作者:Dehui Zhang、Chengye Yuan
DOI:10.1016/j.tet.2007.12.035
日期:2008.3
unexpected enantioselective 1,2-aldol reaction of acetone with α,β-unsaturated trifluoromethylketone catalyzed by l-proline derivative was described. The absolute configuration of the resulting chiral product was assigned based on a single crystal X-ray diffraction analysis. Structure–reactivity study of this organocatalytic system was briefly discussed. A reaction mechanism was tentatively postulated
Reaction of 1,2-Unsaturated Trifluoromethyl Ketones and Their Conversion to 1-(Trifluoromethyl)furan Derivatives
作者:Dehui Zhang、Chengye Yuan
DOI:10.1002/ejoc.200700280
日期:2007.8
to 1-(trifluoromethyl)furanderivatives is reported. 4-Aryl-1,1,1-trifluorobut-3-en-2-one was iodinated and subsequently reduced to give the corresponding alcohol. The resultant iodo compound was then subjected to coupling with phenylacetylene to furnish an (E)-3-aryl-2-(2-phenylethynyl)-1-(trifluoromethyl)allyl alcohol, which could be cyclized by means of AgOTf to furnish a 2-(trifluoromethyl)furan
Isothiourea-Mediated One-Pot Synthesis of Trifluoromethyl Substituted 2-Pyrones
作者:Pei-Pei Yeh、David S. B. Daniels、David B. Cordes、Alexandra M. Z. Slawin、Andrew D. Smith
DOI:10.1021/ol403697h
日期:2014.2.7
A one-potisothiourea-mediated Michael addition/lactonization/thiol elimination cascade sequence for the formation of 4,6-disubstituted and 3,4,6-trisubstituted 2-pyrones from (phenylthio)acetic acids and α,β-unsaturated trifluoromethyl ketones is described. The synthesis of a COX-2 inhibitor and the wide-ranging derivatization of the 2-pyrone moiety to trifluoromethyl substituted aromatics and heteroaromatics