One-pot three-component Mannich reactions of ketone, aromatic aldehyde and aromatic amines were e... more One-pot three-component Mannich reactions of ketone, aromatic aldehyde and aromatic amines were efficiently catalyzed by recyclable heterogeneous L-Cysteine supported on ZnS nanoparticles at the ambient temperature to give various β-amino carbonyl compounds with high yields. This simple method has some advantages such as mild condition and no environmental pollution. Structures of the compounds were confirmed by 1 H NMR and IR spectral analyses. ZnS nanoparticles were prepared in hydrothermal procedure from an aqueous solution of Zinc acetate and NaS in the presence of L-Cysteine. L-Cysteine supported on ZnS nanoparticles was characterized by FT-IR, TEM, TGA/DTA and XRD analysis.
Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB... more Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB) of cis-enol forms of 1-(npyridyl)butane-1,3-diones (nPBD) (n = 2, 3, or 4) have been investigated by means of density functional theory (DFT) calculations. Energy differences for all possible nPBD cis-enol forms of isomers with respect to the most stable form of the corresponding isomer have been estimated in the gas phase and solution. AIM results (performed at the B3LYP/6-311++G** level) suggest 75.19-84.77 kJ mol -1 for the strength of intramolecular hydrogen bond in these systems, as a medium hydrogen bond strength. Theoretical structure, NBO and intramolecular hydrogen bond strength for the stable cis-enol forms of nPBD have been compared with each other and also with those of acetylacetone (AA), benzoylacetone (BA), and triflouroacetylacetone (TFAA) molecules. The hydrogen bond strength and molecular stability are investigated by applying the NBO, topological analysis, geometry calculations, and spectroscopic results. The correlation between IHB and some parameters related to hydrogen bonding have been also investigated.
One-pot three-component Mannich reactions of ketone, aromatic aldehyde and aromatic amines were e... more One-pot three-component Mannich reactions of ketone, aromatic aldehyde and aromatic amines were efficiently catalyzed by recyclable heterogeneous L-Cysteine supported on ZnS nanoparticles at the ambient temperature to give various β-amino carbonyl compounds with high yields. This simple method has some advantages such as mild condition and no environmental pollution. Structures of the compounds were confirmed by 1 H NMR and IR spectral analyses. ZnS nanoparticles were prepared in hydrothermal procedure from an aqueous solution of Zinc acetate and NaS in the presence of L-Cysteine. L-Cysteine supported on ZnS nanoparticles was characterized by FT-IR, TEM, TGA/DTA and XRD analysis.
journal of sciences islamic republic of iran, Jan 12, 2003
A one-pot synthesis of (S)-(-)-propranolol is reported. Zn(NO 3 ) 2 /(+)-tartaric acid catalyzed ... more A one-pot synthesis of (S)-(-)-propranolol is reported. Zn(NO 3 ) 2 /(+)-tartaric acid catalyzed enantioselective synthesis of (S)-(-)-propranolol via kinetic resolution of key intermediate α-naphthyl glycidyl ether with high optical and chemical yield.
Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB... more Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB) of cis-enol forms of 1-(npyridyl)butane-1,3-diones (nPBD) (n = 2, 3, or 4) have been investigated by means of density functional theory (DFT) calculations. Energy differences for all possible nPBD cis-enol forms of isomers with respect to the most stable form of the corresponding isomer have been estimated in the gas phase and solution. AIM results (performed at the B3LYP/6-311++G** level) suggest 75.19-84.77 kJ mol -1 for the strength of intramolecular hydrogen bond in these systems, as a medium hydrogen bond strength. Theoretical structure, NBO and intramolecular hydrogen bond strength for the stable cis-enol forms of nPBD have been compared with each other and also with those of acetylacetone (AA), benzoylacetone (BA), and triflouroacetylacetone (TFAA) molecules. The hydrogen bond strength and molecular stability are investigated by applying the NBO, topological analysis, geometry calculations, and spectroscopic results. The correlation between IHB and some parameters related to hydrogen bonding have been also investigated.
Ferric hydrogensulfate catalyzed the synthesis of 5-substituted 1H-tetrazoles via [2 + 3] cycload... more Ferric hydrogensulfate catalyzed the synthesis of 5-substituted 1H-tetrazoles via [2 + 3] cycloaddition of nitriles and sodium azide. This method has the advantages of high yields, simple methodology, and easy workup. The catalyst can be recovered by simple filtration and reused delivering good yields. Also, ferric hydrogensulfate catalyzed the hydrolysis of nitriles to primary amides under aqueous conditions. Various aliphatic and aromatic nitriles converted to the corresponding amides in good yields without any contamination with carboxylic acids.
journal of sciences islamic republic of iran, Jan 12, 2003
A one-pot synthesis of (S)-(-)-propranolol is reported. Zn(NO 3 ) 2 /(+)-tartaric acid catalyzed ... more A one-pot synthesis of (S)-(-)-propranolol is reported. Zn(NO 3 ) 2 /(+)-tartaric acid catalyzed enantioselective synthesis of (S)-(-)-propranolol via kinetic resolution of key intermediate α-naphthyl glycidyl ether with high optical and chemical yield.
Iranian Journal of Science and Technology (Sciences), Jun 20, 2004
A facile and efficient method for the preparation of 1, 1-diacetates of aldehydes is improved. P ... more A facile and efficient method for the preparation of 1, 1-diacetates of aldehydes is improved. P 2 O 5 /SiO 2 catalyzed 1, 1-diacetates formation from aldehydes in dry media. Advantages of this method are the use of an inexpensive and selective catalyst with high yields in simple operation and short reaction time under solvent-free conditions.
Ferric hydrogensulfate catalyzed the synthesis of 5-substituted 1H-tetrazoles via [2 + 3] cycload... more Ferric hydrogensulfate catalyzed the synthesis of 5-substituted 1H-tetrazoles via [2 + 3] cycloaddition of nitriles and sodium azide. This method has the advantages of high yields, simple methodology, and easy workup. The catalyst can be recovered by simple filtration and reused delivering good yields. Also, ferric hydrogensulfate catalyzed the hydrolysis of nitriles to primary amides under aqueous conditions. Various aliphatic and aromatic nitriles converted to the corresponding amides in good yields without any contamination with carboxylic acids.
Iranian Journal of Science and Technology (Sciences), Jun 20, 2004
A facile and efficient method for the preparation of 1, 1-diacetates of aldehydes is improved. P ... more A facile and efficient method for the preparation of 1, 1-diacetates of aldehydes is improved. P 2 O 5 /SiO 2 catalyzed 1, 1-diacetates formation from aldehydes in dry media. Advantages of this method are the use of an inexpensive and selective catalyst with high yields in simple operation and short reaction time under solvent-free conditions.
Bis [S-allyl-β-N-(benzylidene)dithiocarbazato]copper(II) complex was grafted into SiO2 matrix. He... more Bis [S-allyl-β-N-(benzylidene)dithiocarbazato]copper(II) complex was grafted into SiO2 matrix. Heterogenized catalyst was characterized by FT-IR, SEM, EDX TEM, N2 absorption and atomic absorption spectroscopy (AAS) and its catalytic performance in the oxidation of alcohols was investigated. The experimental results showed that the prepared heterogeneous nanocatalyst is an efficient and selective catalyst for examined oxidation reaction. Thus, secondary alcohols were oxidized to ketones and primery alcohols converted to aldehydes by hydrogen peroxide in the presence of newly nanocatalyst in mild conditions.
Bis [S-allyl-β-N-(benzylidene)dithiocarbazato]copper(II) complex was grafted into SiO2 matrix. He... more Bis [S-allyl-β-N-(benzylidene)dithiocarbazato]copper(II) complex was grafted into SiO2 matrix. Heterogenized catalyst was characterized by FT-IR, SEM, EDX TEM, N2 absorption and atomic absorption spectroscopy (AAS) and its catalytic performance in the oxidation of alcohols was investigated. The experimental results showed that the prepared heterogeneous nanocatalyst is an efficient and selective catalyst for examined oxidation reaction. Thus, secondary alcohols were oxidized to ketones and primery alcohols converted to aldehydes by hydrogen peroxide in the presence of newly nanocatalyst in mild conditions.
Cyclocondensation of 2-[bis(methylthio)methylene]malononitrile (1) and cysteamine (2) afforded 2-... more Cyclocondensation of 2-[bis(methylthio)methylene]malononitrile (1) and cysteamine (2) afforded 2-(thiazolidin-2-ylidene)malononitrile (3). This compound on treatment with NaSH gave the corresponding thioamide derivative 4a in a regioselective manner on the basis of its single crystal X-ray diffraction analysis. Reaction of this compound with several α-bromocarbonyl compounds gave new 2-(E)-cyano(thiazolidin-2ylidene)thiazoles 5a-g.
Some new compounds based on bis-benzimidazole moieties have been synthesized and characterized by... more Some new compounds based on bis-benzimidazole moieties have been synthesized and characterized by IR and NMR spectroscopies. The ability of 3a in transition metal cation sensing such as Co 2+ , Ni 2+ , Zn 2+ , Mn 2+ , Fe 2+ and Cu 2+ have been investigated by UV-Vis and fluorescence spectroscopy in methanol solvent. The complexation constants and complex stoichiometry of Cu 2+ have been determined. The experimental result shows that 3a exhibits high selectivity toward Cu 2+ cation in a 1:1 complex stoichiometry. The absorption bond and the fluorescence intensity have been increased by addition of successive amount of Cu 2+ solution in methanol. Therefore, these results demonstrate that, the compound can be used as a sensor to detect Cu 2+ cation via absorption and emission spectroscopy.
Facilitated transport of silver(I) cation across a bulk liquid membrane by two synthesized ligand... more Facilitated transport of silver(I) cation across a bulk liquid membrane by two synthesized ligands, bis-β-enamino ester (BBEE) and bis(benzoic acid) trioxaheptane (BBAT), as carriers dissolved in dichloromethane has been investigated. BBEE was used as a specific ion carrier for the transport of silver(I) ion. The influence of experimental parameters affecting the transport efficiency of silver(I) ion have been studied. In the presence of thiosulfate as a suitable metal ion acceptor in the receiving phase and picrate ion as ion pairing agent in the source phase, the amount of silver(I) ion transported across the liquid membrane after 120 min was found to be 97%. Tolerance to the presence of different ions was investigated and it was found that silver(I) cation transport was not affected even in the presence of 10-fold concentration of these metal cations in solution. This system was applied for the recovery of silver(I) cation from silver plating and photographic waste solution.
A novel podand based anion receptor bearing benzimidazole motifs as recognition sites was designe... more A novel podand based anion receptor bearing benzimidazole motifs as recognition sites was designed and synthesized by reaction of 1,7-bis(2'-methylbenzoate)-1,4,7-trioxaheptane and phenylenediamine. The binding properties of anionic guest with this receptor were studied using UV-Vis and fluorescence spectroscopy. These studies revealed that this receptor exhibit selective recognition towards F -ion among other anions such as HSO 4 -, ClO 4 -, Cl -, Br -and I -in methanol through intermolecular hydrogen bonding of guest and host. Also, we have focused our attention on the receptor-F -with theoretical computation based on DFT/B3LYP/6-31G(d).
were synthesized by a one-pot microwave-assisted procedure in good yields. Irradiation of diols a... more were synthesized by a one-pot microwave-assisted procedure in good yields. Irradiation of diols and dichlorides in the presence of sodium hydroxide in DMSO gave title crown ethers presumably within a template effect.
Nano-sized NiLa2O4 spinel was produced by thermal decomposition of Ni-La compounds via a sol-gel ... more Nano-sized NiLa2O4 spinel was produced by thermal decomposition of Ni-La compounds via a sol-gel method. The well-crystallized spinel structure was formed after calcination at 750 °C. The physicochemical properties of the spinel were investigated using differential thermal analysis, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and particle size distribution analysis. The results show that the nanoparticles have regular shapes with well-defined crystal faces and consist of uniform quasi-spherical crystallites of average size 40 nm. The refined unit cell parameters are a = 3.861205 Å and c = 12.6793 Å. This new nano-sized NiLa2O4 spinel is an efficient heterogeneous catalyst for the selective conversion of imines to the corresponding secondary amines in the presence of NaBH4 as a reducing agent, in good to excellent yields. All the reactions were completely chemoselective at room temperature and had relatively short reaction times. Secondary amines with different aryl groups, including those bearing electron-withdrawing or electron-donating groups, were obtained under the optimum reaction conditions. The catalyst was readily recovered and was recycled four times with no significant loss of catalytic activity.
One-pot three-component Mannich reactions of ketone, aromatic aldehyde and aromatic amines were e... more One-pot three-component Mannich reactions of ketone, aromatic aldehyde and aromatic amines were efficiently catalyzed by recyclable heterogeneous L-Cysteine supported on ZnS nanoparticles at the ambient temperature to give various β-amino carbonyl compounds with high yields. This simple method has some advantages such as mild condition and no environmental pollution. Structures of the compounds were confirmed by 1 H NMR and IR spectral analyses. ZnS nanoparticles were prepared in hydrothermal procedure from an aqueous solution of Zinc acetate and NaS in the presence of L-Cysteine. L-Cysteine supported on ZnS nanoparticles was characterized by FT-IR, TEM, TGA/DTA and XRD analysis.
Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB... more Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB) of cis-enol forms of 1-(npyridyl)butane-1,3-diones (nPBD) (n = 2, 3, or 4) have been investigated by means of density functional theory (DFT) calculations. Energy differences for all possible nPBD cis-enol forms of isomers with respect to the most stable form of the corresponding isomer have been estimated in the gas phase and solution. AIM results (performed at the B3LYP/6-311++G** level) suggest 75.19-84.77 kJ mol -1 for the strength of intramolecular hydrogen bond in these systems, as a medium hydrogen bond strength. Theoretical structure, NBO and intramolecular hydrogen bond strength for the stable cis-enol forms of nPBD have been compared with each other and also with those of acetylacetone (AA), benzoylacetone (BA), and triflouroacetylacetone (TFAA) molecules. The hydrogen bond strength and molecular stability are investigated by applying the NBO, topological analysis, geometry calculations, and spectroscopic results. The correlation between IHB and some parameters related to hydrogen bonding have been also investigated.
One-pot three-component Mannich reactions of ketone, aromatic aldehyde and aromatic amines were e... more One-pot three-component Mannich reactions of ketone, aromatic aldehyde and aromatic amines were efficiently catalyzed by recyclable heterogeneous L-Cysteine supported on ZnS nanoparticles at the ambient temperature to give various β-amino carbonyl compounds with high yields. This simple method has some advantages such as mild condition and no environmental pollution. Structures of the compounds were confirmed by 1 H NMR and IR spectral analyses. ZnS nanoparticles were prepared in hydrothermal procedure from an aqueous solution of Zinc acetate and NaS in the presence of L-Cysteine. L-Cysteine supported on ZnS nanoparticles was characterized by FT-IR, TEM, TGA/DTA and XRD analysis.
journal of sciences islamic republic of iran, Jan 12, 2003
A one-pot synthesis of (S)-(-)-propranolol is reported. Zn(NO 3 ) 2 /(+)-tartaric acid catalyzed ... more A one-pot synthesis of (S)-(-)-propranolol is reported. Zn(NO 3 ) 2 /(+)-tartaric acid catalyzed enantioselective synthesis of (S)-(-)-propranolol via kinetic resolution of key intermediate α-naphthyl glycidyl ether with high optical and chemical yield.
Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB... more Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB) of cis-enol forms of 1-(npyridyl)butane-1,3-diones (nPBD) (n = 2, 3, or 4) have been investigated by means of density functional theory (DFT) calculations. Energy differences for all possible nPBD cis-enol forms of isomers with respect to the most stable form of the corresponding isomer have been estimated in the gas phase and solution. AIM results (performed at the B3LYP/6-311++G** level) suggest 75.19-84.77 kJ mol -1 for the strength of intramolecular hydrogen bond in these systems, as a medium hydrogen bond strength. Theoretical structure, NBO and intramolecular hydrogen bond strength for the stable cis-enol forms of nPBD have been compared with each other and also with those of acetylacetone (AA), benzoylacetone (BA), and triflouroacetylacetone (TFAA) molecules. The hydrogen bond strength and molecular stability are investigated by applying the NBO, topological analysis, geometry calculations, and spectroscopic results. The correlation between IHB and some parameters related to hydrogen bonding have been also investigated.
Ferric hydrogensulfate catalyzed the synthesis of 5-substituted 1H-tetrazoles via [2 + 3] cycload... more Ferric hydrogensulfate catalyzed the synthesis of 5-substituted 1H-tetrazoles via [2 + 3] cycloaddition of nitriles and sodium azide. This method has the advantages of high yields, simple methodology, and easy workup. The catalyst can be recovered by simple filtration and reused delivering good yields. Also, ferric hydrogensulfate catalyzed the hydrolysis of nitriles to primary amides under aqueous conditions. Various aliphatic and aromatic nitriles converted to the corresponding amides in good yields without any contamination with carboxylic acids.
journal of sciences islamic republic of iran, Jan 12, 2003
A one-pot synthesis of (S)-(-)-propranolol is reported. Zn(NO 3 ) 2 /(+)-tartaric acid catalyzed ... more A one-pot synthesis of (S)-(-)-propranolol is reported. Zn(NO 3 ) 2 /(+)-tartaric acid catalyzed enantioselective synthesis of (S)-(-)-propranolol via kinetic resolution of key intermediate α-naphthyl glycidyl ether with high optical and chemical yield.
Iranian Journal of Science and Technology (Sciences), Jun 20, 2004
A facile and efficient method for the preparation of 1, 1-diacetates of aldehydes is improved. P ... more A facile and efficient method for the preparation of 1, 1-diacetates of aldehydes is improved. P 2 O 5 /SiO 2 catalyzed 1, 1-diacetates formation from aldehydes in dry media. Advantages of this method are the use of an inexpensive and selective catalyst with high yields in simple operation and short reaction time under solvent-free conditions.
Ferric hydrogensulfate catalyzed the synthesis of 5-substituted 1H-tetrazoles via [2 + 3] cycload... more Ferric hydrogensulfate catalyzed the synthesis of 5-substituted 1H-tetrazoles via [2 + 3] cycloaddition of nitriles and sodium azide. This method has the advantages of high yields, simple methodology, and easy workup. The catalyst can be recovered by simple filtration and reused delivering good yields. Also, ferric hydrogensulfate catalyzed the hydrolysis of nitriles to primary amides under aqueous conditions. Various aliphatic and aromatic nitriles converted to the corresponding amides in good yields without any contamination with carboxylic acids.
Iranian Journal of Science and Technology (Sciences), Jun 20, 2004
A facile and efficient method for the preparation of 1, 1-diacetates of aldehydes is improved. P ... more A facile and efficient method for the preparation of 1, 1-diacetates of aldehydes is improved. P 2 O 5 /SiO 2 catalyzed 1, 1-diacetates formation from aldehydes in dry media. Advantages of this method are the use of an inexpensive and selective catalyst with high yields in simple operation and short reaction time under solvent-free conditions.
Bis [S-allyl-β-N-(benzylidene)dithiocarbazato]copper(II) complex was grafted into SiO2 matrix. He... more Bis [S-allyl-β-N-(benzylidene)dithiocarbazato]copper(II) complex was grafted into SiO2 matrix. Heterogenized catalyst was characterized by FT-IR, SEM, EDX TEM, N2 absorption and atomic absorption spectroscopy (AAS) and its catalytic performance in the oxidation of alcohols was investigated. The experimental results showed that the prepared heterogeneous nanocatalyst is an efficient and selective catalyst for examined oxidation reaction. Thus, secondary alcohols were oxidized to ketones and primery alcohols converted to aldehydes by hydrogen peroxide in the presence of newly nanocatalyst in mild conditions.
Bis [S-allyl-β-N-(benzylidene)dithiocarbazato]copper(II) complex was grafted into SiO2 matrix. He... more Bis [S-allyl-β-N-(benzylidene)dithiocarbazato]copper(II) complex was grafted into SiO2 matrix. Heterogenized catalyst was characterized by FT-IR, SEM, EDX TEM, N2 absorption and atomic absorption spectroscopy (AAS) and its catalytic performance in the oxidation of alcohols was investigated. The experimental results showed that the prepared heterogeneous nanocatalyst is an efficient and selective catalyst for examined oxidation reaction. Thus, secondary alcohols were oxidized to ketones and primery alcohols converted to aldehydes by hydrogen peroxide in the presence of newly nanocatalyst in mild conditions.
Cyclocondensation of 2-[bis(methylthio)methylene]malononitrile (1) and cysteamine (2) afforded 2-... more Cyclocondensation of 2-[bis(methylthio)methylene]malononitrile (1) and cysteamine (2) afforded 2-(thiazolidin-2-ylidene)malononitrile (3). This compound on treatment with NaSH gave the corresponding thioamide derivative 4a in a regioselective manner on the basis of its single crystal X-ray diffraction analysis. Reaction of this compound with several α-bromocarbonyl compounds gave new 2-(E)-cyano(thiazolidin-2ylidene)thiazoles 5a-g.
Some new compounds based on bis-benzimidazole moieties have been synthesized and characterized by... more Some new compounds based on bis-benzimidazole moieties have been synthesized and characterized by IR and NMR spectroscopies. The ability of 3a in transition metal cation sensing such as Co 2+ , Ni 2+ , Zn 2+ , Mn 2+ , Fe 2+ and Cu 2+ have been investigated by UV-Vis and fluorescence spectroscopy in methanol solvent. The complexation constants and complex stoichiometry of Cu 2+ have been determined. The experimental result shows that 3a exhibits high selectivity toward Cu 2+ cation in a 1:1 complex stoichiometry. The absorption bond and the fluorescence intensity have been increased by addition of successive amount of Cu 2+ solution in methanol. Therefore, these results demonstrate that, the compound can be used as a sensor to detect Cu 2+ cation via absorption and emission spectroscopy.
Facilitated transport of silver(I) cation across a bulk liquid membrane by two synthesized ligand... more Facilitated transport of silver(I) cation across a bulk liquid membrane by two synthesized ligands, bis-β-enamino ester (BBEE) and bis(benzoic acid) trioxaheptane (BBAT), as carriers dissolved in dichloromethane has been investigated. BBEE was used as a specific ion carrier for the transport of silver(I) ion. The influence of experimental parameters affecting the transport efficiency of silver(I) ion have been studied. In the presence of thiosulfate as a suitable metal ion acceptor in the receiving phase and picrate ion as ion pairing agent in the source phase, the amount of silver(I) ion transported across the liquid membrane after 120 min was found to be 97%. Tolerance to the presence of different ions was investigated and it was found that silver(I) cation transport was not affected even in the presence of 10-fold concentration of these metal cations in solution. This system was applied for the recovery of silver(I) cation from silver plating and photographic waste solution.
A novel podand based anion receptor bearing benzimidazole motifs as recognition sites was designe... more A novel podand based anion receptor bearing benzimidazole motifs as recognition sites was designed and synthesized by reaction of 1,7-bis(2'-methylbenzoate)-1,4,7-trioxaheptane and phenylenediamine. The binding properties of anionic guest with this receptor were studied using UV-Vis and fluorescence spectroscopy. These studies revealed that this receptor exhibit selective recognition towards F -ion among other anions such as HSO 4 -, ClO 4 -, Cl -, Br -and I -in methanol through intermolecular hydrogen bonding of guest and host. Also, we have focused our attention on the receptor-F -with theoretical computation based on DFT/B3LYP/6-31G(d).
were synthesized by a one-pot microwave-assisted procedure in good yields. Irradiation of diols a... more were synthesized by a one-pot microwave-assisted procedure in good yields. Irradiation of diols and dichlorides in the presence of sodium hydroxide in DMSO gave title crown ethers presumably within a template effect.
Nano-sized NiLa2O4 spinel was produced by thermal decomposition of Ni-La compounds via a sol-gel ... more Nano-sized NiLa2O4 spinel was produced by thermal decomposition of Ni-La compounds via a sol-gel method. The well-crystallized spinel structure was formed after calcination at 750 °C. The physicochemical properties of the spinel were investigated using differential thermal analysis, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and particle size distribution analysis. The results show that the nanoparticles have regular shapes with well-defined crystal faces and consist of uniform quasi-spherical crystallites of average size 40 nm. The refined unit cell parameters are a = 3.861205 Å and c = 12.6793 Å. This new nano-sized NiLa2O4 spinel is an efficient heterogeneous catalyst for the selective conversion of imines to the corresponding secondary amines in the presence of NaBH4 as a reducing agent, in good to excellent yields. All the reactions were completely chemoselective at room temperature and had relatively short reaction times. Secondary amines with different aryl groups, including those bearing electron-withdrawing or electron-donating groups, were obtained under the optimum reaction conditions. The catalyst was readily recovered and was recycled four times with no significant loss of catalytic activity.
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Papers by Hossein Eshghi