Various xanthenes have been synthesized by the condensation ofβ-naphthol,2-hydroxynaphthalene-1,4-dione or dimedone with various aldehydes in the presence of trifluoroacetic acid as catalyst in 1,1,3,3-N,N,N′,N′-te...Various xanthenes have been synthesized by the condensation ofβ-naphthol,2-hydroxynaphthalene-1,4-dione or dimedone with various aldehydes in the presence of trifluoroacetic acid as catalyst in 1,1,3,3-N,N,N′,N′-tetramethylguanidinium trifluoroacetate (TMGT) ionic liquid within 1 h at 75℃.展开更多
Nine 3,3’-(arylmethylene)bis(2-hydroxynaphthalene-1,4-dione) derivatives were synthesized through the reaction between 2-hydroxy-1,4-naphthalen-1,4-dione and different aromatic alde-hydes in water applying ultrasonic...Nine 3,3’-(arylmethylene)bis(2-hydroxynaphthalene-1,4-dione) derivatives were synthesized through the reaction between 2-hydroxy-1,4-naphthalen-1,4-dione and different aromatic alde-hydes in water applying ultrasonic irradiation for 5 min at room temperature and microwave irradiation for 15 min at 70°;C. Two of the nine derivatives, compounds 3-e and 3-i, obtained from 3-bromo-hydroxybenzaldehyde and 5-methylfuran-2-carbaldehyde, respectively, are previously unpublished. The structures of all compounds were established on the basis of their spectral data and mass analysis. The attractive features of this synthesis protocol include mild conditions, high atom-economy and excellent yields with the elimination of water as the only by-product.展开更多
A direct regioselective preparation of 2-hydroxynaphthalene-6-carboxylic acid, a useful industrial intermediate of aro-matic polyester from 2-naphthol was conducted by use of excess amount of K2CO3 (10-fold molar to 2...A direct regioselective preparation of 2-hydroxynaphthalene-6-carboxylic acid, a useful industrial intermediate of aro-matic polyester from 2-naphthol was conducted by use of excess amount of K2CO3 (10-fold molar to 2-naphthol) under supercritical CO2 at 10 MPa and 473 K. The obtained yield under this condition was ca. 20 mol% to 2-naphthol. The further investigations may provide an alternative process to the conventional Kolbe-Schmitt reaction, because of no use of strong alkali and recoverability of K2CO3. Theoretical explanation about the regioselectivity was achieved by means of DFT calculations.展开更多
A simple and efficient protocol has been developed for the synthesis of 3-phenylnaphtho[2,3-b]furan-4,9-diones by domino reaction of a-bromonitroalkenes to 2-hydroxynaphthalene-1,4-dione. With the optimal reaction con...A simple and efficient protocol has been developed for the synthesis of 3-phenylnaphtho[2,3-b]furan-4,9-diones by domino reaction of a-bromonitroalkenes to 2-hydroxynaphthalene-1,4-dione. With the optimal reaction condi- tions [NaOAc (120 mol%), water, 70 ~C, 7 h], the scope of the domino reaction was explored and the green ap- proach provided the desired products in moderate to good yields at elevated temperature under aqueous-mediated conditions. A mechanistic rationalization for this reaction is also provided. The absorption characteristics of the compounds were examined by UV-Vis spectra and fluorescence spectroscopy. All compounds were fluorescent in solution emitting at blue light (432--433 nm), green light (512--536 nm), or yellow light (591 nm).展开更多
A simple and facile synthesis of 12-arylbenzo[g]indeno[2,1-b]quinoline-6,11,13-trione deriv-atives was accomplished by the one-pot condensation of 2-hydroxynaphthalene-1,4-dione, aryl aldehydes, 2H-indene-1,3-dione, a...A simple and facile synthesis of 12-arylbenzo[g]indeno[2,1-b]quinoline-6,11,13-trione deriv-atives was accomplished by the one-pot condensation of 2-hydroxynaphthalene-1,4-dione, aryl aldehydes, 2H-indene-1,3-dione, and ammonium acetate under solvent-free conditions in the presence of a Brnsted ionic liquid catalyst, namely 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate.展开更多
An efficient method for the synthesis of 2-amino-3-cyano-4-aryl-5,10-dioxo-5,10-dihydro-4H- ben-zo[g]chromenes and hydroxy-substituted naphthalene-1,4-dione derivatives, using silica-bonded propylpiperazine-N-sulfamic...An efficient method for the synthesis of 2-amino-3-cyano-4-aryl-5,10-dioxo-5,10-dihydro-4H- ben-zo[g]chromenes and hydroxy-substituted naphthalene-1,4-dione derivatives, using silica-bonded propylpiperazine-N-sulfamic acid as a solid acid, green, heterogeneous catalyst, under ambient and solvent-free conditions, is described. A simple procedure, high yields, short reaction time, safety, and reusability of the catalyst are advantages of these protocols.展开更多
In this study,Au nanoparticles/poly 5-[(2-hydroxynaphthalen-l-yl)diazenyl]isophthalic acid film modified glassy carbon electrode(AuNPs/poly(NDI)/GCE) has shown excellent electrocatalytic activity toward the oxid...In this study,Au nanoparticles/poly 5-[(2-hydroxynaphthalen-l-yl)diazenyl]isophthalic acid film modified glassy carbon electrode(AuNPs/poly(NDI)/GCE) has shown excellent electrocatalytic activity toward the oxidation of adrenaline(ADR),paracetamol(PAC),and tryptophan(Trp).The bare glassy carbon electrode(GCE) fails to separate the oxidation peak potentials of these molecules,while the poly(NDI) film modified electrode can resolve them.Electrochemical impedance spectroscopy(EIS)indicates that the charge transfer resistance of the bare electrode decreases as 5-[(2-hydroxynaphthalen-l-yl)diazenyl]isophthalic acid is electropolymerized on the bare electrode.Furthermore,EIS exhibits enhancement of electron transfer kinetics between analytes and the electrode after electrodeposition of Au nanoparticles.Differential pulse voltammetry results show that the electrocatalytic current increases linearly in the ranges of 0.01-680.0 μmol L^-1 for ADR,0.05-498.0 μmol L^-1 for PAC,and 3.0-632.0 μmol L^-1 for Trp;with detection limits(S/N = 3) of 0.009 μmol L^-1,0.005 μmol L^-1,and 0.09 μmol L^-1 for ADR,PAC,and Trp,respectively.The proposed method has been successfully applied for simultaneous determination of ADR,PAC,and Trp in biological samples.展开更多
基金the financial support of the Research Council of the University of Isfahan.
文摘Various xanthenes have been synthesized by the condensation ofβ-naphthol,2-hydroxynaphthalene-1,4-dione or dimedone with various aldehydes in the presence of trifluoroacetic acid as catalyst in 1,1,3,3-N,N,N′,N′-tetramethylguanidinium trifluoroacetate (TMGT) ionic liquid within 1 h at 75℃.
文摘Nine 3,3’-(arylmethylene)bis(2-hydroxynaphthalene-1,4-dione) derivatives were synthesized through the reaction between 2-hydroxy-1,4-naphthalen-1,4-dione and different aromatic alde-hydes in water applying ultrasonic irradiation for 5 min at room temperature and microwave irradiation for 15 min at 70°;C. Two of the nine derivatives, compounds 3-e and 3-i, obtained from 3-bromo-hydroxybenzaldehyde and 5-methylfuran-2-carbaldehyde, respectively, are previously unpublished. The structures of all compounds were established on the basis of their spectral data and mass analysis. The attractive features of this synthesis protocol include mild conditions, high atom-economy and excellent yields with the elimination of water as the only by-product.
文摘A direct regioselective preparation of 2-hydroxynaphthalene-6-carboxylic acid, a useful industrial intermediate of aro-matic polyester from 2-naphthol was conducted by use of excess amount of K2CO3 (10-fold molar to 2-naphthol) under supercritical CO2 at 10 MPa and 473 K. The obtained yield under this condition was ca. 20 mol% to 2-naphthol. The further investigations may provide an alternative process to the conventional Kolbe-Schmitt reaction, because of no use of strong alkali and recoverability of K2CO3. Theoretical explanation about the regioselectivity was achieved by means of DFT calculations.
文摘A simple and efficient protocol has been developed for the synthesis of 3-phenylnaphtho[2,3-b]furan-4,9-diones by domino reaction of a-bromonitroalkenes to 2-hydroxynaphthalene-1,4-dione. With the optimal reaction condi- tions [NaOAc (120 mol%), water, 70 ~C, 7 h], the scope of the domino reaction was explored and the green ap- proach provided the desired products in moderate to good yields at elevated temperature under aqueous-mediated conditions. A mechanistic rationalization for this reaction is also provided. The absorption characteristics of the compounds were examined by UV-Vis spectra and fluorescence spectroscopy. All compounds were fluorescent in solution emitting at blue light (432--433 nm), green light (512--536 nm), or yellow light (591 nm).
文摘A simple and facile synthesis of 12-arylbenzo[g]indeno[2,1-b]quinoline-6,11,13-trione deriv-atives was accomplished by the one-pot condensation of 2-hydroxynaphthalene-1,4-dione, aryl aldehydes, 2H-indene-1,3-dione, and ammonium acetate under solvent-free conditions in the presence of a Brnsted ionic liquid catalyst, namely 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate.
文摘An efficient method for the synthesis of 2-amino-3-cyano-4-aryl-5,10-dioxo-5,10-dihydro-4H- ben-zo[g]chromenes and hydroxy-substituted naphthalene-1,4-dione derivatives, using silica-bonded propylpiperazine-N-sulfamic acid as a solid acid, green, heterogeneous catalyst, under ambient and solvent-free conditions, is described. A simple procedure, high yields, short reaction time, safety, and reusability of the catalyst are advantages of these protocols.
文摘In this study,Au nanoparticles/poly 5-[(2-hydroxynaphthalen-l-yl)diazenyl]isophthalic acid film modified glassy carbon electrode(AuNPs/poly(NDI)/GCE) has shown excellent electrocatalytic activity toward the oxidation of adrenaline(ADR),paracetamol(PAC),and tryptophan(Trp).The bare glassy carbon electrode(GCE) fails to separate the oxidation peak potentials of these molecules,while the poly(NDI) film modified electrode can resolve them.Electrochemical impedance spectroscopy(EIS)indicates that the charge transfer resistance of the bare electrode decreases as 5-[(2-hydroxynaphthalen-l-yl)diazenyl]isophthalic acid is electropolymerized on the bare electrode.Furthermore,EIS exhibits enhancement of electron transfer kinetics between analytes and the electrode after electrodeposition of Au nanoparticles.Differential pulse voltammetry results show that the electrocatalytic current increases linearly in the ranges of 0.01-680.0 μmol L^-1 for ADR,0.05-498.0 μmol L^-1 for PAC,and 3.0-632.0 μmol L^-1 for Trp;with detection limits(S/N = 3) of 0.009 μmol L^-1,0.005 μmol L^-1,and 0.09 μmol L^-1 for ADR,PAC,and Trp,respectively.The proposed method has been successfully applied for simultaneous determination of ADR,PAC,and Trp in biological samples.