Eskandar Kolvari | Semnan University (original) (raw)

Papers by Eskandar Kolvari

Research paper thumbnail of Ultrasound assisted-dispersive-modification solid-phase extraction using task-specific ionic liquid immobilized on multiwall carbon nanotubes for speciation and determination mercury in water samples

Microchemical Journal

Abstract An efficient method based on 1-(3-aminopropyl)-3-methylimidazolium hexafluorophosphate (... more Abstract An efficient method based on 1-(3-aminopropyl)-3-methylimidazolium hexafluorophosphate (TSIL) immobilized on multiwall carbon nanotubes (MWCNTs@ [Apmim][PF6]) was used for speciation of inorganic/organic mercury (Hg2+, R-Hg or O-Hg) by ultrasound assisted-dispersive modification solid-phase extraction (UAS-DM-SPE) which was combined with cold vapor atomic absorption spectrometry (CV-AAS). The mixture of MWCNTs @ [Apmim][PF6] in acetone was injected to water samples in polypropylene syringe filters (PSF) which was already adjusted pH up to 8.5. After shaking, the Hg(II) and O-Hg were simply extracted on amine group of [Apmim][PF6] as TSIL and then, separated from the liquid phase by pushing plunger of PSF. The Hg(II) and O-Hg loaded in MWCNTs @ [Apmim][PF6] were back-extracted based on the eluent solution (HNO3, 0.5 mL, 0.2 mol L−1) with/without microwave system (UV radiation at 165 °C). Finally, the concentration of mercury was determined by CV-AAS. By microwave, organic mercury species in remained solution were changed to Hg (II) and the total amount of mercury (T-Hg) was determined. Finally, O-Hg concentration was computed by subtracting the Hg (II) concentration from T-Hg. Under the optimized conditions, the linear range, LOD and enrichment factor for Hg (II) and O-Hg were achieved (0.02–3.6 μg L−1; 0.02–3.4 μg L−1), (5.2 ng L−1; 5.8 ng L−1) and (19.9; 19.7), respectively (Mean of RSD

Research paper thumbnail of A waste to wealth approach through utilization of nano-Ceramic Tile Waste as an accessible and inexpensive solid support to produce a heterogeneous solid acid nanocatalyst: To kill three birds with one stone

RSC Adv., 2016

Waste minimization through the utilization of cost-effective, available, and nontoxic nano-cerami... more Waste minimization through the utilization of cost-effective, available, and nontoxic nano-ceramic tile wastes for the heterogenization of sulfuric acid.

Research paper thumbnail of Sodium Hydrogen Sulfate: Safe and Efficient

Research paper thumbnail of Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthoperiodic Acid under Mild Conditions

Synthesis-stuttgart, 2009

Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthope... more Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthoperiodic Acid under Mild Conditions. -Treatment of aromatic amines with potassium bromide and orthoperiodic acid in a two-phase system affords monobromo products in good to high yields. Bromination of unactivated aromatic compounds and aromatic ketones fails, while phenolic substrates give a sluggish reaction. The bromination procedure is extended to alkenes and alkynes affording trans-configurated bromo compounds in short times. This method avoids the use of toxic, pure molecular bromine since it only appears as an intermediate. -(KHAZAEI*, A.; ZOLFIGOL, M. A.; KOLVARI, E.; KOUKABI, N.; SOLTANI, H.; KOMAKI, F.; Synthesis 2009, 21, 3672-3676; Fac. Chem., Bu-Ali Sina Univ., Hamedan, Iran; Eng.) -H. Hoennerscheid 10-042

Research paper thumbnail of Green synthesis of quinoxaline derivatives using p-dodecylbenzensulfonic acid as a surfactant-type Bronsted acid catalyst in water

Green Chemistry Letters and Reviews, 2011

Quinoxaline derivatives have been synthesized in high yields in the presence of p-dodecylbenzensu... more Quinoxaline derivatives have been synthesized in high yields in the presence of p-dodecylbenzensulfulfonic acid as an inexpensive, nontoxic, and efficient Bronsted acid-surfactant-combined catalyst in water at room temperature.

Research paper thumbnail of H 5 IO 6 /KI: A New Combination Reagent for Iodination of Aromatic Amines, and Trimethylsilylation of Alcohols and Phenols through in situ Generation of Iodine under Mild Conditions

Helvetica Chimica Acta, 2010

A combination of iodic acid and potassium iodide has been used for trimethylsilylation of alcohol... more A combination of iodic acid and potassium iodide has been used for trimethylsilylation of alcohols and phenols in the presence of HMDS and iodination of aromatic amines. The reactions occur very rapidly to provide the products in good to high yields in dichloromethane at room temperature while the use of toxic and corrosive molecular iodine is avoided.

Research paper thumbnail of Synthesis of new tripodal Hantzsch 1,4-dihydropyridines under solvent-free condition and their conversion to the corresponding tripodal pyridines

Molecular Diversity, 2010

A mixture of β-ketoester and tri-aldehydes in the presence of ammonium fluoride was converted to ... more A mixture of β-ketoester and tri-aldehydes in the presence of ammonium fluoride was converted to their corresponding tripodal 1,4-dihydropyridines under solvent-free condition with good yields. The obtained tripodal 1,4-dihydropyridines were also aromatized with oxone®/NaNO2/wet SiO2 system under mild and heterogeneous conditions quantitatively.

Research paper thumbnail of Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Iodic Acid/Potassium Bromide Under Mild Conditions

Synthetic Communications, 2010

Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthope... more Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthoperiodic Acid under Mild Conditions. -Treatment of aromatic amines with potassium bromide and orthoperiodic acid in a two-phase system affords monobromo products in good to high yields. Bromination of unactivated aromatic compounds and aromatic ketones fails, while phenolic substrates give a sluggish reaction. The bromination procedure is extended to alkenes and alkynes affording trans-configurated bromo compounds in short times. This method avoids the use of toxic, pure molecular bromine since it only appears as an intermediate. -(KHAZAEI*, A.; ZOLFIGOL, M. A.; KOLVARI, E.; KOUKABI, N.; SOLTANI, H.; KOMAKI, F.; Synthesis 2009, 21, 3672-3676; Fac. Chem., Bu-Ali Sina Univ., Hamedan, Iran; Eng.) -H. Hoennerscheid 10-042

Research paper thumbnail of Surfactant-assisted synthesis of bis(indolyl)methanes in water

Chinese Chemical Letters, 2011

An environmentally friendly synthesis method for bis(indolyl)methanes has been developed in the p... more An environmentally friendly synthesis method for bis(indolyl)methanes has been developed in the presence of sodium lauryl ether sulfate (SLES), electrophilic substitution reactions of indoles with aldehydes were accomplished in water as solvent at room temperature without any Bronested or Lewis acid catalysts.

Research paper thumbnail of Ultrasound Promoted One-Pot Synthesis of gem-Chloronitro Compounds from Oximes

Organic Preparations and Procedures International, 2012

ABSTRACT

Research paper thumbnail of A simple and efficient route for the synthesis of di and tri(bis(indolyl) methanes) as new triarylmethanes

Molecular Diversity, 2008

Preparation of di and tri(bis(indolyl) methanes) from di and trialdehydes and indoles in the pres... more Preparation of di and tri(bis(indolyl) methanes) from di and trialdehydes and indoles in the presence of silica sulfuric acid was described. Reactions proceeded in good to excellent yields in acetonitrile as solvent at room temperature.

Research paper thumbnail of Green synthesis of quinoxaline derivatives using p-dodecylbenzensulfonic acid as a surfactant-type Bronsted acid catalyst in water

Green Chemistry Letters and Reviews, 2012

Quinoxaline derivatives have been synthesized in high yields in the presence of p-dodecylbenzensu... more Quinoxaline derivatives have been synthesized in high yields in the presence of p-dodecylbenzensulfulfonic acid as an inexpensive, nontoxic, and efficient Bronsted acid-surfactant-combined catalyst in water at room temperature.

Research paper thumbnail of Mild and heterogeneous oxidation of urazoles to their corresponding triazolinediones via in situ generation Cl + using silica sulfuric acid/KClO 3 or silica chloride/oxone system

Catalysis Communications, 2007

A combination of silica sulfuric acid and potassium chlorate or oxone® and silica chloride in the... more A combination of silica sulfuric acid and potassium chlorate or oxone® and silica chloride in the presence of wet SiO2 was used as an effective oxidizing agent for the oxidation of urazoles and bis-urazoles to their corresponding triazolinediones under mild and heterogeneous conditions with moderate to excellent yields.

Research paper thumbnail of Application of N-Halo Reagents in Organic Synthesis

Cheminform, 2007

This review article summarizes published data on the application of N-halo reagents (such as N-ha... more This review article summarizes published data on the application of N-halo reagents (such as N-halo amines, N-halo amides and/or imides, N-halo sulfonamides and/or imides, and etc.) in various organic functional group transformations such as: oxidation reactions, deprotection and protection of different functional groups, halogenation of saturated and unsaturated compounds, acylation of alcohols, phenols, amines or thiols, epoxidation of alkenes, aziridination and etc. The main purpose of writing this review is encouraging of active researchers interested to this field for the synthesis of new N-halo reagents specially with different halogens and applications of these new N-halo reagents in organic reactions or finding more and more applications of existing N-halo reagents in organic synthesis.

Research paper thumbnail of ChemInform Abstract: Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthoperiodic Acid under Mild Conditions

Cheminform, 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Research paper thumbnail of A catalytic and transition metal-free method for the chemoselective oxidation of alcohols to their corresponding carbonyl compounds using periodic acid or iodic acid in the presence of a catalytic amount of KBr

Journal of Molecular Catalysis A-chemical, 2007

Chemoselective oxidation of various alcohols was proceeded by using a catalytic amount of KBr in ... more Chemoselective oxidation of various alcohols was proceeded by using a catalytic amount of KBr in the presence of periodic acid or iodic acid and wet SiO2 under mild and heterogeneous conditions with moderate to excellent yields.

Research paper thumbnail of THE APPLICATION OF N,N′DIBROMO-N,N′-1,2-ETHANEDIYL BIS(P-TOLUENESULFONAMIDE) AS A POWERFUL REAGENT FOR CONVERSION OF CARBOXYLIC ACIDS INTO ESTERS AND AMIDES WITH TRIPHENYLPHOSPHINE

Phosphorus Sulfur and Silicon and The Related Elements, 2004

N,N%-Dibromo-N,N%-1,2-ethanediylbis (p-toluenesulphonamide) [BNBTS] 2 was reacted with oximes and... more N,N%-Dibromo-N,N%-1,2-ethanediylbis (p-toluenesulphonamide) [BNBTS] 2 was reacted with oximes and converts them to their corresponding carbonyl compounds in good yields under mild conditions.

Research paper thumbnail of The Application of N,N?-Dibromo-N,N?-1,2-ethanediyl Bis(p-toluenesulfonamide) as a Powerful Reagent for Conversion of Carboxylic Acids into Esters and Amides with Triphenylphosphine

Cheminform, 2005

N,N%-Dibromo-N,N%-1,2-ethanediylbis (p-toluenesulphonamide) [BNBTS] 2 was reacted with oximes and... more N,N%-Dibromo-N,N%-1,2-ethanediylbis (p-toluenesulphonamide) [BNBTS] 2 was reacted with oximes and converts them to their corresponding carbonyl compounds in good yields under mild conditions.

Research paper thumbnail of Easy Access to Coumarin Derivatives Using Alumina Sulfuric Acid (ASA) as an Efficient and Reusable Catalyst under Solvent-Free Conditions

A new and efficient condition for the use of alumina sulfuric acid (ASA) as a heterogeneous catal... more A new and efficient condition for the use of alumina sulfuric acid (ASA) as a heterogeneous catalyst in the Pechmann condensation reaction in solvent-free condition for the formation of coumarins has been reported.

Research paper thumbnail of Ultrasound assisted-dispersive-modification solid-phase extraction using task-specific ionic liquid immobilized on multiwall carbon nanotubes for speciation and determination mercury in water samples

Microchemical Journal

Abstract An efficient method based on 1-(3-aminopropyl)-3-methylimidazolium hexafluorophosphate (... more Abstract An efficient method based on 1-(3-aminopropyl)-3-methylimidazolium hexafluorophosphate (TSIL) immobilized on multiwall carbon nanotubes (MWCNTs@ [Apmim][PF6]) was used for speciation of inorganic/organic mercury (Hg2+, R-Hg or O-Hg) by ultrasound assisted-dispersive modification solid-phase extraction (UAS-DM-SPE) which was combined with cold vapor atomic absorption spectrometry (CV-AAS). The mixture of MWCNTs @ [Apmim][PF6] in acetone was injected to water samples in polypropylene syringe filters (PSF) which was already adjusted pH up to 8.5. After shaking, the Hg(II) and O-Hg were simply extracted on amine group of [Apmim][PF6] as TSIL and then, separated from the liquid phase by pushing plunger of PSF. The Hg(II) and O-Hg loaded in MWCNTs @ [Apmim][PF6] were back-extracted based on the eluent solution (HNO3, 0.5 mL, 0.2 mol L−1) with/without microwave system (UV radiation at 165 °C). Finally, the concentration of mercury was determined by CV-AAS. By microwave, organic mercury species in remained solution were changed to Hg (II) and the total amount of mercury (T-Hg) was determined. Finally, O-Hg concentration was computed by subtracting the Hg (II) concentration from T-Hg. Under the optimized conditions, the linear range, LOD and enrichment factor for Hg (II) and O-Hg were achieved (0.02–3.6 μg L−1; 0.02–3.4 μg L−1), (5.2 ng L−1; 5.8 ng L−1) and (19.9; 19.7), respectively (Mean of RSD

Research paper thumbnail of A waste to wealth approach through utilization of nano-Ceramic Tile Waste as an accessible and inexpensive solid support to produce a heterogeneous solid acid nanocatalyst: To kill three birds with one stone

RSC Adv., 2016

Waste minimization through the utilization of cost-effective, available, and nontoxic nano-cerami... more Waste minimization through the utilization of cost-effective, available, and nontoxic nano-ceramic tile wastes for the heterogenization of sulfuric acid.

Research paper thumbnail of Sodium Hydrogen Sulfate: Safe and Efficient

Research paper thumbnail of Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthoperiodic Acid under Mild Conditions

Synthesis-stuttgart, 2009

Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthope... more Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthoperiodic Acid under Mild Conditions. -Treatment of aromatic amines with potassium bromide and orthoperiodic acid in a two-phase system affords monobromo products in good to high yields. Bromination of unactivated aromatic compounds and aromatic ketones fails, while phenolic substrates give a sluggish reaction. The bromination procedure is extended to alkenes and alkynes affording trans-configurated bromo compounds in short times. This method avoids the use of toxic, pure molecular bromine since it only appears as an intermediate. -(KHAZAEI*, A.; ZOLFIGOL, M. A.; KOLVARI, E.; KOUKABI, N.; SOLTANI, H.; KOMAKI, F.; Synthesis 2009, 21, 3672-3676; Fac. Chem., Bu-Ali Sina Univ., Hamedan, Iran; Eng.) -H. Hoennerscheid 10-042

Research paper thumbnail of Green synthesis of quinoxaline derivatives using p-dodecylbenzensulfonic acid as a surfactant-type Bronsted acid catalyst in water

Green Chemistry Letters and Reviews, 2011

Quinoxaline derivatives have been synthesized in high yields in the presence of p-dodecylbenzensu... more Quinoxaline derivatives have been synthesized in high yields in the presence of p-dodecylbenzensulfulfonic acid as an inexpensive, nontoxic, and efficient Bronsted acid-surfactant-combined catalyst in water at room temperature.

Research paper thumbnail of H 5 IO 6 /KI: A New Combination Reagent for Iodination of Aromatic Amines, and Trimethylsilylation of Alcohols and Phenols through in situ Generation of Iodine under Mild Conditions

Helvetica Chimica Acta, 2010

A combination of iodic acid and potassium iodide has been used for trimethylsilylation of alcohol... more A combination of iodic acid and potassium iodide has been used for trimethylsilylation of alcohols and phenols in the presence of HMDS and iodination of aromatic amines. The reactions occur very rapidly to provide the products in good to high yields in dichloromethane at room temperature while the use of toxic and corrosive molecular iodine is avoided.

Research paper thumbnail of Synthesis of new tripodal Hantzsch 1,4-dihydropyridines under solvent-free condition and their conversion to the corresponding tripodal pyridines

Molecular Diversity, 2010

A mixture of β-ketoester and tri-aldehydes in the presence of ammonium fluoride was converted to ... more A mixture of β-ketoester and tri-aldehydes in the presence of ammonium fluoride was converted to their corresponding tripodal 1,4-dihydropyridines under solvent-free condition with good yields. The obtained tripodal 1,4-dihydropyridines were also aromatized with oxone®/NaNO2/wet SiO2 system under mild and heterogeneous conditions quantitatively.

Research paper thumbnail of Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Iodic Acid/Potassium Bromide Under Mild Conditions

Synthetic Communications, 2010

Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthope... more Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthoperiodic Acid under Mild Conditions. -Treatment of aromatic amines with potassium bromide and orthoperiodic acid in a two-phase system affords monobromo products in good to high yields. Bromination of unactivated aromatic compounds and aromatic ketones fails, while phenolic substrates give a sluggish reaction. The bromination procedure is extended to alkenes and alkynes affording trans-configurated bromo compounds in short times. This method avoids the use of toxic, pure molecular bromine since it only appears as an intermediate. -(KHAZAEI*, A.; ZOLFIGOL, M. A.; KOLVARI, E.; KOUKABI, N.; SOLTANI, H.; KOMAKI, F.; Synthesis 2009, 21, 3672-3676; Fac. Chem., Bu-Ali Sina Univ., Hamedan, Iran; Eng.) -H. Hoennerscheid 10-042

Research paper thumbnail of Surfactant-assisted synthesis of bis(indolyl)methanes in water

Chinese Chemical Letters, 2011

An environmentally friendly synthesis method for bis(indolyl)methanes has been developed in the p... more An environmentally friendly synthesis method for bis(indolyl)methanes has been developed in the presence of sodium lauryl ether sulfate (SLES), electrophilic substitution reactions of indoles with aldehydes were accomplished in water as solvent at room temperature without any Bronested or Lewis acid catalysts.

Research paper thumbnail of Ultrasound Promoted One-Pot Synthesis of gem-Chloronitro Compounds from Oximes

Organic Preparations and Procedures International, 2012

ABSTRACT

Research paper thumbnail of A simple and efficient route for the synthesis of di and tri(bis(indolyl) methanes) as new triarylmethanes

Molecular Diversity, 2008

Preparation of di and tri(bis(indolyl) methanes) from di and trialdehydes and indoles in the pres... more Preparation of di and tri(bis(indolyl) methanes) from di and trialdehydes and indoles in the presence of silica sulfuric acid was described. Reactions proceeded in good to excellent yields in acetonitrile as solvent at room temperature.

Research paper thumbnail of Green synthesis of quinoxaline derivatives using p-dodecylbenzensulfonic acid as a surfactant-type Bronsted acid catalyst in water

Green Chemistry Letters and Reviews, 2012

Quinoxaline derivatives have been synthesized in high yields in the presence of p-dodecylbenzensu... more Quinoxaline derivatives have been synthesized in high yields in the presence of p-dodecylbenzensulfulfonic acid as an inexpensive, nontoxic, and efficient Bronsted acid-surfactant-combined catalyst in water at room temperature.

Research paper thumbnail of Mild and heterogeneous oxidation of urazoles to their corresponding triazolinediones via in situ generation Cl + using silica sulfuric acid/KClO 3 or silica chloride/oxone system

Catalysis Communications, 2007

A combination of silica sulfuric acid and potassium chlorate or oxone® and silica chloride in the... more A combination of silica sulfuric acid and potassium chlorate or oxone® and silica chloride in the presence of wet SiO2 was used as an effective oxidizing agent for the oxidation of urazoles and bis-urazoles to their corresponding triazolinediones under mild and heterogeneous conditions with moderate to excellent yields.

Research paper thumbnail of Application of N-Halo Reagents in Organic Synthesis

Cheminform, 2007

This review article summarizes published data on the application of N-halo reagents (such as N-ha... more This review article summarizes published data on the application of N-halo reagents (such as N-halo amines, N-halo amides and/or imides, N-halo sulfonamides and/or imides, and etc.) in various organic functional group transformations such as: oxidation reactions, deprotection and protection of different functional groups, halogenation of saturated and unsaturated compounds, acylation of alcohols, phenols, amines or thiols, epoxidation of alkenes, aziridination and etc. The main purpose of writing this review is encouraging of active researchers interested to this field for the synthesis of new N-halo reagents specially with different halogens and applications of these new N-halo reagents in organic reactions or finding more and more applications of existing N-halo reagents in organic synthesis.

Research paper thumbnail of ChemInform Abstract: Electrophilic Bromination of Alkenes, Alkynes, and Aromatic Amines with Potassium Bromide/Orthoperiodic Acid under Mild Conditions

Cheminform, 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Research paper thumbnail of A catalytic and transition metal-free method for the chemoselective oxidation of alcohols to their corresponding carbonyl compounds using periodic acid or iodic acid in the presence of a catalytic amount of KBr

Journal of Molecular Catalysis A-chemical, 2007

Chemoselective oxidation of various alcohols was proceeded by using a catalytic amount of KBr in ... more Chemoselective oxidation of various alcohols was proceeded by using a catalytic amount of KBr in the presence of periodic acid or iodic acid and wet SiO2 under mild and heterogeneous conditions with moderate to excellent yields.

Research paper thumbnail of THE APPLICATION OF N,N′DIBROMO-N,N′-1,2-ETHANEDIYL BIS(P-TOLUENESULFONAMIDE) AS A POWERFUL REAGENT FOR CONVERSION OF CARBOXYLIC ACIDS INTO ESTERS AND AMIDES WITH TRIPHENYLPHOSPHINE

Phosphorus Sulfur and Silicon and The Related Elements, 2004

N,N%-Dibromo-N,N%-1,2-ethanediylbis (p-toluenesulphonamide) [BNBTS] 2 was reacted with oximes and... more N,N%-Dibromo-N,N%-1,2-ethanediylbis (p-toluenesulphonamide) [BNBTS] 2 was reacted with oximes and converts them to their corresponding carbonyl compounds in good yields under mild conditions.

Research paper thumbnail of The Application of N,N?-Dibromo-N,N?-1,2-ethanediyl Bis(p-toluenesulfonamide) as a Powerful Reagent for Conversion of Carboxylic Acids into Esters and Amides with Triphenylphosphine

Cheminform, 2005

N,N%-Dibromo-N,N%-1,2-ethanediylbis (p-toluenesulphonamide) [BNBTS] 2 was reacted with oximes and... more N,N%-Dibromo-N,N%-1,2-ethanediylbis (p-toluenesulphonamide) [BNBTS] 2 was reacted with oximes and converts them to their corresponding carbonyl compounds in good yields under mild conditions.

Research paper thumbnail of Easy Access to Coumarin Derivatives Using Alumina Sulfuric Acid (ASA) as an Efficient and Reusable Catalyst under Solvent-Free Conditions

A new and efficient condition for the use of alumina sulfuric acid (ASA) as a heterogeneous catal... more A new and efficient condition for the use of alumina sulfuric acid (ASA) as a heterogeneous catalyst in the Pechmann condensation reaction in solvent-free condition for the formation of coumarins has been reported.