HY zeolites catalyze the crossed aldol condensation of acetophenone with benzaldehyde, in benzene at 80 C, to give trans- and cis-chalcones. Together with these expected products, 3,3-diphenylpropiophenone is also produced. In the analogous basic condensation, using phase transfer catalysis, the Michael adduct was not detected, and besides chalcone a small percentage of the Cannizzaro reaction product was observed.
Synthesis Of Chalcone From Acetophenone And Benzaldehyde Pdf Download
Chalcones are structural derivatives of 1,3-diphenylprop-2-en-1-one. They are ubiquitous in natural products and belong to the family of flavonoids examples licochalcone A (1) licochalcone D (2) and morachalcone A (3)9,10. They have been reportedly used as anticancer11,12, antidiabetics13, antioxidants14, antimalarial15,16, antitubercular17,18, antiviral19, anti-inflammatory20,21, antibacterial22,23 agents etc. Furthermore, chalcones are industrially used as light stabilizing agent24, sweetening agent25, analytical reagent in amperometry26, spectrometric reagent27 and synthetic reagent for the synthesis of pharmacologically active heterocyclic compounds28,29,30.
The synthesis of 3, in the presence of 1.00 mL of MeOH as the solvent, and aqueous base with different concentrations from 6 to 14 M, together with ultrasound-assisted (UA), afforded the highest yield of 3 (39.7 %) when the reaction was carried out at KOH 10 M (Table 1, entry 3). When comparing the synthesis of 5 and that of 3, both were synthesized from 3,4-dihydroxybenzaldehyde (1a), differed only in acetophenone derivatives. In this case, we used 2ʹ,4ʹ-dihydroxyacetophenone (2b), a more polar substrate than acetophenone (2a). The use of MeOH solvent was not necessary because both substrates were dissolved in alkaline solution well; and highest yield of 5 (33.4 %) was afforded when KOH 14 M (Table 1, entry 10) was used.
Sappanchalcone (7) was synthesized by the reaction of 4ʹ-hydroxy-2ʹ-methoxyacetophenone (2c) with 3,4-dihydroxybenzaldehyde (1a) (Scheme 2). However, 4ʹ-hydroxy-2ʹ-methoxyacetophenone (2c) has not been yet widely commercialized. It was synthesized by the acetylation of 3-methoxyphenol and acetic acid in the presence of polyphosphoric acid (P2O5 > 85 %) as a catalyst (Nagai et al. 1984; Nakazawa 1954). However, this reaction also obtained two other by-products with significant yield: 2ʹ-hydroxy-4ʹ-methoxyacetophenone (2d) and 3ʹ-acetyl-2ʹ-hydroxy-4ʹ-methoxyacetophenone (2e).
Synthesis of sappanchalcone (7). Reagent and conditions: a CH3COOH, polyphosphoric acid, 60 C, 30 min; b 2ʹ,4ʹ-dihydroxyacetophenone, KOH 12 M, ultrasound-assisted, 80 C, 8 h
Bioactivity of chalcone depended largely on amount and properties of substituents on two phenyl rings. Especially the hydroxyl groups were considered as key substituents that significantly enhance the activity of chalcone derivatives. Therefore, we carried out the O-methylation and O-acetylation reactions of some reactants and chalcones, to diversify the chalcone derivatives. For this purpose, (1) the O-methylation reaction on three substrates: 3,4-dihydroxybenzaldehyde (1a), 2,4-dihydroxybenzaldehyde (1c) and 2ʹ,4ʹ-dihydroxyacetophenone (2b); (2) the O-methylation reaction on two products: 3,4-dihydroxychalcone (3) and 3,4,2ʹ,4ʹ-tetrahydroxychalcone (5); and (3) the O-acetylation reaction on 3,4,2ʹ,4ʹ-tetrahydroxychalcone (5) were carried out. With these schemes, ten chalcone derivatives: 3,2ʹ,4ʹ-trihydroxy-4-methoxychalcone (8); 2ʹ,4ʹ-dihydroxy-3,4-dimethoxychalcone (9); 3,4,2ʹ-trihydroxy-4ʹ-methoxychalcone (10); 3,4-dihydroxy-2ʹ,4ʹ-dimethoxychalcone (11); 2,2ʹ,4ʹ-trihydroxy-4-methoxychalcone (12); 3ʹ-caffeoyl-3,4,2ʹ-trihydroxy-4ʹ-methoxychalcone (13); 3-hydroxy-4-methoxychalcone (14); 3,4-dimethoxychalcone (15); 2ʹ-hydroxy-3,4,4ʹ-trimethoxychalcone (16); and 3,4,4ʹ-triacetoxy-2ʹ-hydroxychalcone (17) were obtained (Scheme 3). NMR data validated the formation of these chalcones (Additional file 1). Moreover, two novel chalcones (13 and 17) were also identified by HRMS data (Additional file 1).
2.0 mmol of benzaldehyde derivatives [276.2 mg of 3,4-dihydroxybenzaldehyde (1a); 106.1 mg of benzaldehyde (1b)] and 1.0 mmol of acetophenone derivatives [120.2 mg of acetophenone (2a); 152.2 mg of 2ʹ,4ʹ-dihydroxyacetophenone (2b)] were dissolved in 1.00 mL MeOH, then 1.00 mL KOH 10 M was added. The flask containing the resulting mixture was suspended in the ultrasonic water bath at 70 C for 6 h.
2.0 mmol of benzaldehyde derivatives [275.9 mg of 3,4-dihydroxybenzaldehyde (1a); 276.3 mg of 2,4-dihydroxy benzaldehyde (1c)] and 1.0 mmol of 2ʹ,4ʹ-dihydroxyacetophenone (2b) (152.1 mg) were dissolved in 1.00 mL H2O, then 1.00 mL KOH 14 M was added. The flask containing the resulting mixture was suspended in the ultrasonic water bath at 80 C for 8 h.
The benzaldehyde derivatives (1a, 1d, 1e, or 1f) and the appropriate acetophenone derivatives (2b, 2d, 2e, or 2f) were dissolved in 1.00 mL H2O (except for the experiment carried out with 1e or 2f, which was dissolved in 1.00 mL MeOH), then added 1.00 mL KOH 12 M. The flask containing the resulting mixture was suspended in ultrasonic water bath at 80 C for 8 h. The desired products were obtained by the following work-up: the reaction mixtures were acidified with HCl 3 M to pH 5; the solutions were allowed to cool slowly to 0 C to precipitate crude products. These were recrystallized with MeOH:H2O (1:3) to afford pure chalcones.
A new series of some transition metal complexes were prepared from reaction mix ligands of new azo-chalcone with imidazole and Co, Ni, Cu, Zn and Cd (II) ions. New azo-chalcone prepared by two steps from reacted 4-bromo benzaldehyde with 4-aminoacetophenone to obtain chalcone after that reacted with paracetamol to result new azo-chalcone. The results show that the mole ratio (metal - ligand) is (1:2:2) for all the complexes under study. The ligand characterized by 1HNMR, mass spectrum and its complexes were characterized by microanalysis of the elements, UV-vis, FTIR, molar conduction and magnetic moment. Azo- chalcone coordinated via (N) atom of azo group and (O) atom of OH group of paracetamol with metal ions. Based on the obtained results, an octahedral geometry was proposed for all chelate complexes. The effect of the biological examination of Cd (II) complex was tested antitumor Breast cancer cells and compared with healthy cells to show the possibility of using these compounds in a therapeutic manner.
Equimolar quantities of substituted acetophenone (0.01 mol) and substituted benzaldehyde (0.01 mol) were mixed with ZnO nanoparticle (1 mmol, 0.081g), SnCl2.H2O (10%) and 5mL of distilled water. The reaction mixture was heated at 60C on water bath for 4 hrs. The progress of the reaction was monitored using TLC in n-hexane: EtOAc (3:2) solvent system. After completion of the reaction, the mixture were cooled to room temperature and stirred with ethanol (50 mL) for 30 min and centrifuged for 10 min at 5000 rpm. The resulting liquid on the top solid was collected and concentrated under reduced pressure. The product was purified using column chromatography on silica gel using gradual increasing the polarity of solvent.
Through new concise and facile green synthesis methodology has been was explored to prepare chalcone derivatives containing benzenesulfonamide segment and their antibacterial properties were evaluated. In this work through a green synthesis protocol chalcone and chalcone-sulfonamide hybrids compounds were synthesized from commercially available materials. The starting material p-nitroacetophenone was reduced to p-aminoacetophenone using Fe powder/CaCl2 in EtOH-H2O mixture (Figures S1-S3). The resulting p-aminoacetophenone (4) reacted with substituted benzaldehyde to provide amino chalcone derivatives (Scheme 1). p-aminoacetophenone subsequently subjected to either benzenesulfonyl chloride or 4-methyl benzene sulfonyl chloride under reflux in methanol to afford the corresponding sulfonamide 5a and 5b (Figures S4 and S5). Compound 5a and 5b were used as a starting materials for ZnO NPs catalyzed Claisen-Schmidt type condensation reaction with substituted aromatic aldehydes to obtain chalcone-sulfonamide hybrids 8 and 9 (Figures S11-S14) and with the same reaction procedure compounds 6 and 7 synthesized, starting from p-aminoacetophenone (Figures S6-S10). The overall sequence of reactions used in the synthesis of various targeted chalcone derivatives are illustrated in Scheme 1. The structure elucidations of the synthesized compounds were accomplished using UV-Vis, FTIR, and NMR spectroscopic methods.Scheme 1 Synthesis of chalcone and chalcone-sulfonamide hybrids using ZnO NPs catalyzed reaction.
Objective: Ionic liquids have emerged as powerful tools for molecular organic solvents. Theirwide liquid range, easy recovery, and reusability make them a greener alternative to volatile organicsolvents. Thus, in the present work, our objective was to employ them as dual catalysts and solventsystems for the synthesis of chalcone via the CS condensation.
Methods: In a typical experiment, benzaldehyde (10 mmol), acetophenone (10 mmol), and 2.5mol% (L-AAIL) ionic liquid were mixed in a 50 mL round-bottom flask. The reaction was proceededquickly at room temperature with stirring, and the resulting mixture became a biphasic systemwith the precipitate at the bottom and the upper phase containing some unreacted substratewhich was separated from the catalyst by filtration and decantation. The catalyst was extractedwith CH2Cl2 and separated for the next cycle. 2ff7e9595c
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