Enaminones in the Synthesis of Heterocycles by Microwave Irradiation

Design, synthesis, and herbicidal activity of pyrazole benzophenone derivatives

“…It should be noted that the yield of compound 4 was promoted to 89.5% when reaction time prolonged to 1.5 h and appropriate distilled water added compared with the method of the ref. 26. It might due to that the N 2 H 4 $2HCl dissolved adequately while adding distilled water.…”

“…Compound 3 was synthesized according to the ref. 26. A mixture of 1,3-diphenylpropane-1,3-dione (2.24 g, 10 mmol) and dimethylformamide dimethylacetal (1.19 g, 10 mmol) in anhydrous toluene (50 mL) was heated and reuxed for 8 h, then cooled to room temperature.…”

“…Mp: 131-132 C; 1 Synthesis of phenyl-(3-phenyl-1H-pyrazol-4-yl) methanone (4) Synthesis of compound 4 was based on the method presented earlier. [26][27][28][29] Compound 3 (2.7 g, 10 mmol) was treated with N 2 H 4 $2HCl (1.04 g, 10 mmol) and reuxed in ethanol for 1.5 h, and appropriate distilled water was added to the solution before heating. The faint yellow solid product was obtained, ltered and recrystallized from ethanol.…”

Facile and Straightforward Method Leading to Substituted 4-Amino-1-arylpyrazoles

“…b-Enaminones are, thanks to their ability to react with wide variety of both electrophilic and nucleophilic agents, 1 versatile intermediates in many synthetic transformations, especially in heterocyclic syntheses. [2][3][4][5][6][7][8] b-Enaminones are also important precursors and building blocks for syntheses of many biologically active compounds, such as dopamine agonists, 9 acetylcholinesterase inhibitors, 10 anticonvulsants, 11 alkaloids, 12 and antiinflammatory 13 and antitumor 14 drugs. Chiral enaminones are useful ligands for diastereoselective syntheses.…”

Phosphotungstic Acid Catalysed Synthesis of β-Enamino Compounds under Solvent-Free Conditions

“…25 b-Enamino compounds have been extensively used as intermediates in organic synthesis. [26][27][28][29] In particular, they have been utilised as synthons for the synthesis of various biologically active heterocyclic compounds having antiinflammatory, antitumor, antibacterial, and anticonvulsant activities [30][31] and as intermediates for the preparation of b-enaminoacids, g-enaminoaclohols, and b-enamino esters. 32 Due to its wide range of utility in the pharmaceutical industry, the enamination of β-dicarbonyl compounds with various amines has become an important transformation and consequently several methods have been developed for the synthesis of these compounds.…”