55536-72-6

Upstream product

• 5396-89-4 benzyl acetoacetate 
• 67-68-5 dimethyl sulfoxide 
• 127-19-5 N,N-dimethyl acetamide 
• 67-56-1 methanol 

Relevant academic research and scientific papers

Copper-Catalyzed Oxidative Coupling of β-Keto Esters with N-Methylamides for the Synthesis of Symmetrical 2,3,5,6-Tetrasubstituted Pyridines

A copper-catalyzed oxidative formal [2+2+1+1] cycloaddition for the synthesis of symmetrical tetrasubstituted pyridines was first demonstrated. The reaction is involved in a domino cross-dehydrogenative coupling (CDC) of β-keto esters and N-methylamides, the C-N bond cleavage, the Michael addition, and a condensation and oxidative aromatization process. Multiple C-C and C-N bonds were constructed in one pot via the C-H and C-N cleavage of N-methylamides, which were employed as the carbon source of pyridines. The preliminary mechanistic studies revealed that the C(sp3)-H bond cleavage of N-methylamides was the rate-determining step.

Method for preparing 2,6-dialkyl-3,5-diester group symmetrical pyridine

The invention discloses a method for preparing 2,6-dialkyl-3,5-diester group symmetrical pyridine. The method specifically comprises the following steps: with beta-keto ester as a reaction substrate,a metallic copper compound as a catalyst, a peroxide reagent as an oxidizing agent, ammonium acetate as a nitrogen source, and methanol as a carbon source (also serving as an organic solvent), performing methanol oxidation, dehydration condensation, nucleophilic addition and oxidative aromatization reaction, thereby obtaining the symmetrical 2,6-dialkyl-3,5-diester group symmetrical pyridine. Thepreparation method disclosed by the invention has the characteristics of readily available raw materials, cheap and lowly-toxic catalyst, high catalytic efficiency, simple convenient operation, environmental protection and the like.

Preparation method of 2,3,5,6-tetra-substituted symmetric pyridine

The invention discloses a preparation method of 2,3,5,6-tetra-substituted symmetric pyridine. Specifically, the symmetric 2,3,5,6-tetra-substituted pyridine is prepared by taking beta-ketonic ester as a reaction substrate, a metal copper compound as a catalyst, a peroxide reagent as an oxidizing agent, inorganic ammonium salt as a nitrogen source and N-methylformamides as an organic solvent (also as a carbon source) and through carbon-hydrogen and carbon-nitrogen removal, dehydration condensation and an oxidation aromatization reaction. The preparation method disclosed by the invention has the characteristics of easily available raw materials, cheap and low-toxic catalyst, high catalytic efficiency, wide substrate range, simple and convenient operation, greenness and environmental friendliness and the like.

One-Pot Synthesis of Hantzsch Pyridines via NH4I Promoted Condensation of 1,3-Dicarbonyl Compounds with DMSO and NH4OAc

A one-pot synthesis of Hantzsch pyridines was achieved through NH4I-promoted condensation of 1,3-dicarbonyl compounds with DMSO and NH4OAc, in which the C4 of the pyridine rings was derived from DMSO and the nitrogen atom resulted from NH4OAc and NH4I. The target product could be obtained in moderate to excellent yields.