4350-45-2

Upstream product

• 35929-79-4 4-(4-chloro-phenyl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxylic acid diethyl ester 
• 104-88-1 4-chlorobenzaldehyde 
• 26456-05-3 10-methylacridinium perchlorate 
• 141-97-9 ethyl acetoacetate 
• 631-61-8 ammonium acetate 
• 873-76-7 para-Chlorobenzyl alcohol 

Downstream Products

• 4350-52-1 4-(4-chlorophenyl)-2,6-dimethyl-3,5-pyridinedicarboxylic acid 
• 42455-47-0 ethyl 2,5-dimethyl-4-(4’-chlorophenyl)-1H-pyrrole-3-carboxylate 
• 98918-01-5 4-(4-Chloro-phenyl)-2-methyl-5-oxo-5,6-dihydro-[1,6]naphthyridine-3-carboxylic acid ethyl ester 

Relevant academic research and scientific papers

N-Nitroso-2-aryl-1,3-oxazolidines catalyzed aromatization of Hantzsch 1,4-dihydropyridines

A catalytic amount of N-nitroso-2-aryl-1,3-oxazolidines leading to the aromatization of Hantzsch 1,4-dihydropyridines (DHPs) was successfully achieved. A catalytic mechanism for the reaction is proposed.

The aromatization of Hantzsch 1,4-dihydropyridines by tetrakis-pyridine cobalt (II) dichromate (TPCD)

Aromatization of Hantzsch 1,4-dihydropyridines (1a-n) were promoted by tetrakis-pyridine cobalt (II) dichromate to yield corresponding pyridine derivatives (2a-n) in moderate to high yields (70-87%). The reaction was carried out under mild and convenient

Aromatization of hantzsch 1,4-dihydropyridines with Dess-Martin periodinane under classical heating and microwave irradiation in solventless system

Hantzsch dihydropyridines were readily oxidized by Dess-Martin periodinane supported onto HNO3/ silica gel under classical heating in dichloromethane and microwave irradiation in solventless system.

Ultrasound-promoted aromatization of Hantzsch 1,4-dihydropyridines by clay-supported cupric nitrate

Various diethyl 1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxylates can be oxidized, in dichloromethane at room temperature, by montmorilonite K-10 clay-supported cupric nitrate. The scope of that procedure and the effects of sonication are discussed.

Superparamagnetic core-shell metal–organic framework Fe3O4@Ni-MOF as efficient catalyst for oxidation of 1,4-dihydropyridines using hydrogen peroxide

A facile and efficient method was described for oxidation of some 3,5-diacyl or 3,5-diester 1,4-dihydropyridines using H2O2 in the presence of superparamagnetic core-shell metal–organic framework Fe3O4@Ni-MOF. The Fe3O4@Ni-MOF has been obtained by Step-by-Step method in which magnetic Fe3O4 magnetic nanoparticles were coated with Ni-MOF using a mercaptoacetic acid linker. The synthesized catalyst was characterized using thermogravimetric analysis, FT-IR spectroscopy, powder X-ray diffraction, field emission scanning electron microscopy and energy-dispersive X-ray analysis. The novel superparamagnetic core-shell metal–organic framework Fe3O4@Ni-MOF revealed high efficiency for oxidation of various 1,4-dihydropyridines using hydrogen peroxide. The Box–Behnken design matrix and the response surface method were applied to investigate the optimization of the reaction conditions. The conditions for optimal reaction yield and time were: amount of catalyst ≈17 mmol, temperature ≈78°C and amount of hydrogen peroxide ≈ 1 ml. A variety of 3,5-diacyl or 3,5-diester 1,4-dihydropyridines with different substituted functional groups have been converted to corresponding pyridines with good to excellent isolated yields using H2O2 and Fe3O4@Ni-MOF. The catalyst was reused up to five times for the oxidation of 1,4-dihydropyridines without a significant loss in catalytic activity. The short reaction times, simplicity of method, good to excellent yields and reusability of catalyst were some advantages of the proposed procedure.

TEMPO supported amine functionalized magnetic titania: a magnetically recyclable catalyst for the aerobic oxidative synthesis of heterocyclic compounds

Abstract: The present protocol uncover a new strategy to synthesize highly efficient solid TEMPO based catalyst in which 4-oxo-TEMPO was covalently tethered to the surface of amine functionalized magnetic titania. The chemical nature and structure of the

Ring-contraction of hantzsch esters and their derivatives to pyrrolesviaelectrochemical extrusion of ethyl acetate out of aromatic rings

Electrochemical ring-contraction of HEs and theirs pyridine derivatives is developed to obtain polysubstituted pyrroles. This process provides an orthogonal utilization of Hantzsch esters for the well-documented application as side chain or hydrogen donors. The formal transformation shows an extrusion of ethyl acetate out of the pyridine ring in a single step. In addition to the novel transformation, we also discovered the Lewis acid's intermolecular control of regioselectivity during an intramolecular electrochemical process. The reaction provides a number of polysubstituted pyrroles that have never been accessed, including pharmaceutical intermediates and photoswitches. An unusual 4-electron continuous reduction drives the unprecedented anionic dearomatization/ring-contraction/rearomatization pathway.

Method for ultrasonically oxidizing hantzsch ester 1, 4-dihydropyridine derivative

The invention relates to the technical field of organic synthesis, and provides a method for ultrasonically oxidizing a hantzsch ester 1, 4-dihydropyridine derivative. The method comprises the following steps: under ultrasonic conditions, carrying out oxi

Trinuclear cis-dioxidomolybdenum(VI) complexes of compartmental C3 symmetric ligands: Synthesis, characterization, DFT study and catalytic application for hydropyridines (Hps) via the Hantzsch reaction

Trinuclear cis-dioxidomolybdenum(VI) complexes of the type [{MoVIO2(MeOH)}3L1-7] (1–7) have been synthesized using tris(H2ONO) donor ligands [H6L1-7 (I–VII)] assembled from benzene-1,3,5-tricarbohydrazide (bthz) and the corresponding salicylaldehyde (sal). All the ligands and the complexes were characterized by numerous techniques, such as FT-IR, UV–visible, NMR (1H and 13C) spectroscopy, electrochemical study, elemental analysis, thermogravimetric study and single crystal X-ray diffraction of the ligand III and complexes 1 and 5. In the presence of H2O2 as an oxidant, these complexes show excellent catalytic potential towards the one-pot three-components [ethyl acetoacetate, benzaldehyde (or its derivatives) and ammonium acetate] dynamic covalent assembly in the Hantzsch reaction. Under solvent free conditions, as high as 98% conversion along with 100% selectivity towards diethyl 2,6-dimethyl-4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate (1,4-DHP) has been achieved in 1 h. Although solvents do not improve the conversion, they do influence the selectivity of the products. With the elapse of time, the conversion of dihydropyridine to the diethyl 2,6-dimethyl-4-phenylpyridine-3,5-dicarboxylate derivative occurs and completes in ca. 10 h with a distinct color change, showing the importance of the catalysts. Efforts have been made to provide suitable reaction pathways for the catalytic reaction based on spectroscopic and density functional theory studies.

Silica-supported ceric ammonium nitrate (CAN): a simple, mild and solid-supported reagent for quickest oxidative aromatization of Hantzsch 1,4-dihydropyridines

An efficient and environmentally benign methodology for the oxidative aromatization of 1,4-dihydropyridines to their corresponding pyridine derivatives is developed. The oxidative aromatization of 1,4-dihydropyridines was explored using silica-supported ceric ammonium nitrate as catalyst in CH3CN with or without sonication at room temperature. This supported catalyst acts as a more efficient oxidising reagent and offers several advantages over other reported reagents in terms of reaction time and yields. The supported reagent is found to be more efficient and selective when compared with its unsupported form. The Belousov–Zhabotinskii reaction was not observed in present reaction. The dealkylation observed in case of 4-n-alkyl/n-alkenyl with other oxidising agents is also not observed in the present case.