Synthesis of 4b,5,10a,11-tetrahydroindeno[1,2-b]quinolin-10-ones from Baylis–Hillman adducts

Stereoselective Three-Component Carbocyclization of 1,7-Enynes with Sulfoxonium Ylides and Water under Photoredox Catalysis

A visible-light-induced photoredox three-component carbocyclization reaction of 1,7-enynes with sulfoxonium ylides and water is reported. The protocol provides a facile entry to structurally valuable highly functionalized cyclopenta[c]quinoline scaffolds in a highly chemoselective and stereoselective manner. Salient features of this method include facile redox-neutral conditions, no requirement of base or other additive, and good functional-group tolerance.

Synthesis of O-Heterocycle Spiro-Fused Cyclopentaquinolinones and Cyclopentaindenes through Visible Light-Induced Radical Cyclization Reactions

Presented herein is an effective and sustainable synthesis of O-heterocycle spiro-fused cyclopentaquinolinone and cyclopentaindene derivatives through light-driven cascade reactions of N-(o-ethynylaryl)acrylamides or 2-(2-(phenylethynyl)benzyl)acrylate with various O-heterocycles. Experimental mechanistic studies revealed that these reactions are initiated by visible light-induced radical formation from O-heterocycle and its regioselective addition onto the acrylamide or acrylate moiety followed by 6-exo-dig and 5-endo-trig cascade radical annulation, which is terminated by single electron oxidation and proton elimination. Compared with previously reported synthetic methods for similar purposes, this newly developed protocol has advantages such as a broad substrate scope, extremely mild reaction conditions, excellent atom-economy, high efficiency, and good compatibility with diverse functional groups. With all of these merits, this method is expected to find wide applications in the related research arena.

Chemo- and regio-selective functionalization of Morita–Baylis–Hillman bromides with anthranilic acid

Nucleophilic substitution products of Morita–Baylis–Hillman adducts and their derivatives are valuable synthons. In an attempt to ameliorate the functionality of these functionalized motifs, we report the regio- and chemo-selective functionalization of Morita–Baylis–Hillman bromides with anthranilic acid.

Ultrasound-promoted access to Baylis-Hillman amines

It is surveyed that the amination of the Baylis-Hillman acetates with primary amines can be dramatically promoted in improved yields and shortened reaction time under ultrasound irradiation than those under conventional stirring. The extensive scope of both amines and acetates are screened to investigate the relationship between substituents and their performance in such transformation.

Regio- and Stereoselective Synthesis of α,β-dehydro-β-amino Esters

A facile method for the regio- and stereoselective synthesis of α,β-dehydro-β-amino esters from acetates of Baylis-Hillman adducts with amines was reported. In the absence of any solvent and catalyst, the present strategy works well for a series of electron deficient and electron rich aromatic amines as well as aliphatic ones.

Functionalization of Baylis - Hillman Bromides with Symmetric and Asymmetric Bifunctional Aromatics

Nucleophilic substitution products of Baylis–Hillman adducts are valuable synthons. In an attempt to improve the functionality of Baylis–Hillman adducts we report the regio- and chemo-selective fuctionalization of Baylis–Hillman bromides with symmetric and asymmetric bifunctional aromatics.

The Baylis–Hillman approach to quinoline derivatives

Baylis-Hillman reactions of 2-nitrobenzaldehydes with various activated alkenes afford adducts that undergo reductive cyclisation to quinoline derivatives. The chemo- and regioselectivity of cyclisation appears to be influenced by the choice of both the substrate and the reagent system, and competing reactions have been observed.

Efficient and direct synthesis of poly-substituted indeno[1,2-b]quinolines assisted by p-toluene sulfonic acid using high-temperature water and microwave heating via one-pot, three-component reaction

Reactions of aldehydes, 1,3-indanedione and enaminones were successfully carried out using p-toluene sulfonic acid (p-TsOH) as a catalyst and high-temperature water as a solvent under microwave irradiation. This method provided several advantages such as rapid reaction times, high yields, and a simple workup procedure. In addition, a possible mechanism to account for the reaction was proposed.

An efficient one-pot, three-component synthesis of indeno[1,2-b]quinoline-9,11(6H,10H)-dione, acridine-1,8(2H,5H)-dione and quinoline-3-carbonitrile derivatives from enaminones

An efficient one-pot, three-component method for the preparation of indeno[1,2-b]quinoline-9,11(6H,10H)-dione, acridine-1,8(2H,5H)-dione and various multi-substituted quinoline-3-carbonitrile derivatives has been developed through the Michael addition to enaminones, which was achieved by both microwave irradiation and conventional heating.