Brønsted‐Acid‐Catalyzed Multicomponent One‐Pot Reaction: Efficient Synthesis of Polysubstituted 1,2‐Dihydropyridines

Abstract

An efficient methodf or the synthesis of 1,2-dihydropyridine derivatives from simple andr eadily available aromatic ketones, DMF,a mines and propargylic alcohols has been developed via aB rønsted-acid-catalyzed multicompo-nent one-pot reaction. This reaction proceeded smoothly under metal-and ligand-free conditions in good yields, leading to functional organic molecules, via as elf-organized sequence.Scheme1.Single Brønsted-acid-catalyzed strategy.Scheme2.Biologicallyactive dihydropyridine and tetrahydropyridine derivatives.

Synthesis of Polysubstituted Pyridine Derivatives via Sequential AlCl3‐Catalyzed Condensation/Aza‐Wittig/Isomerization Reactions and a Study of their Antifungal Activities

“…The overall transformations were conducted in a simple onepot procedure and all compounds 8 were characterized by 1 H NMR, 13 C NMR and HRMS spectral analyses.…”

“…1 H NMR spectra were recorded in CDCl 3 on a Varian Mercury 600 spectrometer and resonances were relative to TMS. 13 C NMR spectra were recorded on a Varian Mercury 600 (150 MHz) with complete proton decoupling spectrophotometers (CDCl 3 : 77.0 ppm). Data are reported as follows: chemical shift, multiplicity (s = single, d = doublet, t = triplet, q = quartet, m = multiplet), coupling constants (Hz) and integration.…”

“…In recent years, Lewis acid catalyzed cyclization reactions have emerged as a promising protocol for the synthesis of a series of heteroarenes. [13] For example, in 2015, Reddy's group applied BF 3 · OEt 2 to construct substituted pyrrolo [2,3-b]quinolone derivatives. [13a] Soon afterwards, Wang's group reported an efficient Iron-catalyzed synthesis of polysubstituted 1,2-dihydropyridine derivatives.…”

Synthesis of diaryl sulfides based on copper-doped OMS-2

“…Later, researchers found that OMS-2 also demonstrated an excellent performance in the field of organic synthetic catalysis when different metal ions were used to modify OMS. Reflux, [15][16][17][18] ball milling, 19 impregnation, 20 and multi-step hydrothermal methods [21][22][23] can produce OMS doped with Cu.…”

Microwave‐Assisted One‐Step Four‐Component Reaction for Synthesis of 1,4‐Dihydropyridines Catalyzed by Triethylamine

“…Low yields and side products are additional problems. Protocols with metal based catalysts (ZnO, ZrO 2 ), Lewis acidic catalysts (FeCl 3 , ZnCl 2 , p‐TsOH) and other methods have been reported with improved conditions. Although, metal basic catalysts were active, most of them are expensive and required more workup such as separation from reaction medium and prior conditioning for reuse.…”