Ahmad Shaabani

Faculty of Chemistry, Shahid Beheshti University, P.O. Box 19396-4716 Tehran, I.R. IRAN

[ 1 ] - Cellulose Sulfuric Acid: As an Efficient Bio Polymer Based Catalyst for the Selective Oxidation of Sulfides and Thiols by Hydrogen Peroxide

Cellulose sulfuric acid as a bio-polymer based solid catalyst efficiently catalyzes the selectively oxidation of sulfides to sulfoxides and thiols to disulfides using hydrogen peroxide as a green oxidant with good yields at room temperature. The developed method offers a number of advantages such as high selectivity, mild reaction conditions, simple operation, cleaner reaction profiles, low...

[ 2 ] - A Rapid Combinatorial Library Synthesis of Benzazolo[2,1-b]quinazolinones and Triazolo[2,1-b]quinazolinones

Benzazolo [2,1-b]quinazolinones and triazolo[2,1-b]quinazolinones were synthesized in high yields by the condensation reaction of an aldehyde and a cyclic  β-diketone with 2 - aminobenzimidazole, 2 - aminobenzothiazole or 1, 2, 4 - triazole derivatives in 1 - butyl - 3 -methylimidazolium bromide as an ionic liquid under classic heating conditions within 5-60 minutes. 

[ 3 ] - 1-Butyl-3-Methylimidazolium Bromide Promoted Selectively Oxidation of Sulfur Compounds by NaBrO3

1-Butyl-3-methylimidazolium bromide ([bmim]Br) as an ionic liquid promoted selectively oxidation of aliphatic and aromatic sulfides to the corresponding sulfoxides and the oxidative coupling of thiols to disulfides by NaBrO3 in excellent yields under neutral conditions.

[ 4 ] - Synthesis of Functionalized Coumarins

The synthesis of functionalized 2-oxo-2H-coumarin derivatives has been studied by a one-pot reaction of o-hydroxybenzaldehyde, ethyl 2-bromoacetate and triphenylphosphine in the presence of catalytic amount of triethyl amine in EtOAc, water or under solvent free conditions. We have found the best results obtained under solvent free condition.

[ 5 ] - Microwave-Assisted Three Component Cyclocondensation Reaction: A Facile Synthesis of Highly Functionalized Cyclohexene Derivatives

Microwave-assisted three component cyclocondensation reactions of aldehydes, amides and dienophiles in the presence of acetic anhydride and para-toluenesulfonic acid as a catalyst to afford the highly substituted cyclohexene derivatives, in relatively good yields after several minutes are reported.

[ 6 ] - A Fast and Efficient Method for the Synthesis of 1,5-Benzodiazepine Derivatives Under Solvent-Free Conditions

Silica sulfuric acid is found to catalyze efficiently the condensation of o-phenylenediamines with various linear and cyclic ketones to afford the corresponding 1,5-benzodiazepines in quantitative yields under solvent-free conditions at room temperature

[ 7 ] - Comparison of Catalytic Effect of Alkali and Alkaline Earth Metals Hydrogen Sulfate: As the Promoter for an Efficient Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones under Solvent-Free Conditions

Alkali and alkaline earth metals hydrogen sulfate catalyzed the one-pot three component condensation reactions of aldehydes, 1,3-dicarbonyl compounds and urea or thiourea under solvent-free conditions leading to 3,4-dihydropyrimidin-2(1H)-ones in high yields at 80 °C. Our results showed that Biginelli reaction not only is pH dependent, but the cation of catalyst plays an importan...

[ 8 ] - Oxidation of Sulfides to Sulfoxides by NaBrO3-NH4Cl in Aqueous Acetonitrile

NaBrO3 combined with NH4Cl is found to be an efficient reagent for the transformation of sulfides into sulfoxides in aqueous and under mild conditions.

[ 9 ] - Rates of Acid-Catalyzed NH Proton Exchange of Enaminones, an 1H NMR Study

: 1H NMR spectra of a series of enaminones R-CO-CH=C(NHCH2Ph)-R  [1, R=CH3; 2, R=C6H5; 3, R=CF3; 4, R=CH2CH2CH2; 5, R=CH2C(CH3)2CH2], were obtained in the presence of trifluoroacetic acid in CDCl3 or DMSO-d6 at 28 °C. S...

[ 10 ] - Addition of Ethyl Alcohol to Triethyl Propargyl Ammonium Bromide

Rearrangement of propargyl amine salt, in the presence of a base was studied and it was concluded that this occurs through an allenic intermediate.

[ 11 ] - Synthesis of Triethyl Propargyl Ammonium Bromide from Triethyl Amine With Propargyl Bromide

The reaction between trimethylamine with propargyl bromide was studied and the structure of triethyl propargyl ammonium bromide was illustrated by 1HNMR, IR, and Mass spectra.

[ 12 ] - Thermal Plasma-processed Natural Hydroxyapatite-MnO2 Nanoparticles as a Reusable and Green Heterogeneous Catalyst for Aerobic Oxidation of Benzylic Alkyl Arenes and Alcohols

In the present work, we have reported the in situ oxidation of manganese (II) acetate to MnO2 nanoparticles through the thermal plasma carbonized natural hydroxyapatite (MnO2/TP-NHAp) as a neoteric sustainable method. Interestingly, the thermal plasma-processed surface of the NHAp shows a great ability for oxidation of the manganese (II) without need of any external oxidizing agents. The cataly...

[ 13 ] - A Novel Strategy of Ugi-4CR/Huisgen 1,3-Dipolar Synthesis of 1H-1,2,3-Triazole-Modified Peptidoimetics

In this protocol, we report a novel approach for the synthesis of a new class of heterocyclic 1H-1,2,3-triazole-modified peptidomimetic compounds. The process consists of an Ugi four-component condensation reaction of amines, an isocyanide, an aldehyde and acids followed by a Huisgen 1,3-dipolar cycloaddition reaction with an azide group in the presence of a catalytic amount of CuSO4</...