Bahareh Sadeghi

BF3.SiO2: An efficient heterogeneous alternative for regio-chemo and stereoselective claisen-schmidt condensation

Under solvent free conditions between 40-50 °C, BF3.SiO2, a mild solid acid catalyst, is applied to regio-chemo and stereoselective Claisen-Schmidt condensation. The procedure is very simple and the products are isolated with an easy workup in good to excellent yields.

SbCl5.SiO2: an efficient alternative for one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles in solvent or under solvent-free condition

In a one-pot four-component reaction, an aldehyde, an amine, benzil and ammonium acetate were condensed for the synthesis of 1,2,4,5-tetrasubstituted imidazoles in the presence of silica supported antimony pentachloride (SbCl5.SiO2) in improved yields. The catalyst is recoverable by simple filtration and can be used in the subsequent reactions.

Nano-sawdust-OSO 3 H as a new, cheap and effective nanocatalyst for one-pot synthesis of pyrano[2,3- d ]pyrimidines

An atom-efficient, three-component synthetic methodology has been developed for the preparation of biologically important pyrano[2,3-d]pyrimidines using nano-sawdust-OSO3H as a new catalyst. The reaction involves the use of barbituric acid or thiobarbituric acid, malononitrile and aldehydes. A wide range of aldehydes is compatible in this reaction, producing excellent yields in short time. The morphology of nanocatalyst (nano-sawdust-OSO3H) was observed using a scanning electron microscopy (SEM). The decomposition steps and thermal stability of the catalyst were investigated by thermal analysis techniques (TGA/DTG). The sawdust-OSO3H surface was studied by energy dispersive X-ray spectroscopy (EDX) method to find out the chemical composition. Also, the vibrational spectrum analysis (FT-IR) of the catalyst has been performed.

Synthesis of nanoparticles silica supported sulfuric acid (NPs SiO2–H2SO4): a solid phase acidic catalyst for one-pot synthesis of 4H-chromene derivatives

Nanostructured SiO2–H2SO)4 has been prepared and shown to efficiently catalyse the one-pot, three-component reaction of an aromatic aldehyde, malononitrile and a cyclic 1,3-diketone at reflux, to afford the corresponding 4H-chromene derivative in high yield. 4H-Chromene derivatives are important pharmacological agents exhibiting spasmolytic, diuretic, anticoagulant, anticancer, and antianaphylactic activities.

BF3.SiO2 nanoparticles: a solid phase acidic catalyst for efficient one-pot Hantzsch synthesis of 1,4-dihydropyridines

The solvent-free Hantzsch reaction between ethyl acetoacetate or 1,3-indandione, an aromatic aldehyde and ammonium acetate catalysed by BF3.SiO2 nanoparticles provided an efficient one-step synthesis of 1,4-dihydropyridines in excellent yields.

A clean and expedient synthesis of spirooxindoles catalyzed by silica–sulfuric acid nanoparticles as an efficient and reusable reagent

An atom-efficient, one-pot, three-component synthetic method, using silica–sulfuric acid nanoparticles as catalyst, has been developed for preparation of biologically important spirooxindoles. The reaction involves the use of isatin or 5-fluoroisatin, malononitrile, and enolizable systems. A wide range of enolizable systems can be used in this reaction, furnishing excellent yields in a short time. The catalyst is recyclable with reproducible results without any loss of its activity. The morphology of the silica–sulfuric acid nanoparticles was observed by scanning electron microscopy. Some of the compounds were new and their structures were deduced by elemental and spectral analysis (IR, 1H NMR, and 13C NMR). Moreover, column chromatography and recrystallization of the products is not required because the crude products are already highly pure.

ZnO Nanoparticles: An Efficient Reagent, Simple and One-Pot Procedure for Synthesis of Highly Functionalized Dihydropyridine Derivatives

A new and efficient one-pot synthesis of dihydropyridones derivatives by four-component reaction between cyanoacetamide, aryl aldehydes, and ethyl acetoacetate with ammonium acetate using nano ZnO is described. The reaction was performed in ethanol under reflux conditions and afforded good yields of products.

Monolayer-protected silver nanoparticles: an efficient and versatile reagent for the synthesis of 3,4-dihydropyrimidine-2-(1 H )-ones (thiones)

Silver nanoparticles has been prepared and shown to efficiently catalyse the one-pot, three-component reaction of an aromatic aldehyde, urea or thiourea and a 1,3-diketone at reflux, to afford the corresponding 3,4-dihydropyrimidine-2-(1H)-ones in high yield.

Nanoparticle silica supported sulfuric acid (NPs SiO 2 -H 2 SO 4 ): a solid phase acidic catalyst for the one-pot synthesis of benzo[ a ]xanthene-11-one derivatives

The reaction between aromatic aldehydes, dimedone (5,5-dimethyl-1,3-cyclohexane dione) and 2-naphthol catalysed by nanoparticle silica supported sulfuric acid (NPs SiO2-H2SO4) in CH2Cl2 as a solvent at room temperature provided a simple and efficient one-pot route for the synthesis of benzo[a]xanthene-11-one derivatives in high yield. Benzoxanthenes are important heterocycles because of their antiviral, anti-inflammatory and antibacterial activities.

Nano-cellulose-OSO3H as a new, green, and effective nano-catalyst for one-pot synthesis of pyrano [4,3-b] pyrans

A facile, green, and efficient method has been developed for the synthesis of biologically important pyrano [4,3-b] pyrans in the presence of nano-cellulose-OSO3H as a new solid acid catalyst. The reaction involves the use of 4-hydroxy-6-methyl-2H-pyran-2-one, malononitrile, and aldehydes. A wide range of aldehydes is compatible in this reaction, producing excellent yields in short time. The morphology of nano-catalyst (nano-cellulose-OSO3H) was observed using a scanning electron microscopy (SEM). The cellulose-OSO3H surface was studied by the energy dispersive X-ray spectroscopy (EDX) method to find out the chemical composition. The decomposition steps and thermal stability of the catalyst were investigated by thermal analysis techniques (TGA/DTG). In addition, the vibrational spectrum analysis (FT-IR) and X-ray diffractogram (XRD) of the catalyst have been performed.