A versatile and efficient synthesis of 3-aroyl-1,4-dihydroquinolin-4-ones
摘要:
A versatile and efficient method for preparation of 3-aroyl-4-quinolones is described. The procedure involved a Michael-type addition of methyl anthranylate with various beta-ketonic enol ethers followed by based promoted cyclisation. Different quinolones have been obtained. The ring closure is facilitated by heating at reflux in diphenyl ether leading to increase the rate of the cyclisation. (C) 2004 Elsevier Ltd. All rights reserved.
Synthesis of symmetrical 2,8-dioxabicyclo[3.3.1]nonanes (4) is accomplished by the reaction of β-enamino ketones (1) and 1,3-cyclohexanediones (2) in AcOH. However, the presence of TFA in toluene gave xanthenes (5).
Palladium-catalyzed cross-coupling reaction of iodobenzene and its 4-substituted derivatives, except for 4-nitroiodobenzene, with (Z)-1-ethoxy-2-(tributylstannyl)ethene under a carbon monoxide atmosphere (5 atm) gave the corresponding (E)-3-ethoxy-1-arylprop-2-en-1-ones in considerable yields. Syntheses of chromone and 4(1H)-quinolinone were accomplished by application of this method to 2-(methoxymethoxy)iodobenzene and ethyl 2-iodophenylcarbanylate, respectively. The results obtained on the carbonylative coupling reaction of halopyridines are also described.
Route to Chiral Tetrahydrofuran Acetals via Pd-Catalyzed Asymmetric Allylic Cycloaddition of Vinyl Epoxides with β-Keto Enol Ethers
作者:Meiqi Li、Yiming Liu、Yong Jian Zhang
DOI:10.1021/acs.orglett.2c02437
日期:2022.9.23
An efficient method for the synthesis of functionalized chiral tetrahydrofuran (THF) acetals via Pd-catalyzed asymmetric allylic cycloaddition has been developed. With a palladium catalyst coordinated by a chiral phosphine ligand, the protocol is enabled to combine readily available vinyl epoxides and β-keto enol ethers to produce THF acetals bearing three stereocenters in a broad substrate scope with
Selective Synthesis of α‐Alkoxy Enones by α‐Addition of Alcohols to Alkynones Using 1,1,1,3,3,3‐Hexafluoroisopropanol and PPh
<sub>3</sub>
as Co‐catalysts
作者:Xiu‐Ming Li、Jing‐Kui Yang
DOI:10.1002/ejoc.202201163
日期:2022.12.19
The α-addition of alcohols to alkynones was demonstrated. A series of α-alkoxy enones can directly be synthesized in moderate to high yields under mild conditions. Mechanism studies were carried out by various means.