Silica-bonded N-propyldiethylenetriamine sulfamic acid (SPDTSA) is employed as a recyclable heterogeneous solid acid catalyst for the synthesis of benzopyrano[2,3-d]pyrimidines  through one-pot condensation reaction of salicylaldehydes, malononitrile and secondary amines  at room temperature under solvent-free conditions. SPDTSA showed much the same efficiency when used in con...

The preparation of bis-thiazolidinones has been achieved by a one-pot condensation reaction of araldehydes, ethylenediamine and thioglycolic acid in the presence of nano-CuCr2O4 nanoparticles under reflux conditions in toluene. This method provides several advantages including easy workup, excellent yields, short reaction times, reusability of the catalyst and low catalyst loading.

A mild and efficient method has been developed for the preparation of substituted coumarins from reaction of various phenols with different β-ketoesters via Pechmann condensation in the presence of Brønsted acidic ionic liquid (N-(4-sulfonic acid) butyl triethylammonium hydrogen sulfate) as an effective catalyst under solvent-free conditions. Different phenols reacted with ethyl acetoacetate to...

melamine trisulfonic acid (mtsa) as an efficient heterogeneous catalyst has been used for the one-pot preparation of triazolo[1,2-a]indazole-1,3,8-trione and 2h-indazolo[2,1-b]phthalazine-1,6,11-trione derivatives by the three-component condensation reaction of urazoles or phthalhydrazide, dimedone or 1,3-cyclohexanedione, and aldehydes under solvent-free conditions in good to excellent yields ...

sulfonic acid functionalized sba-15 as a nanoporous acid catalyst was used in the synthesis of 2-aryl benzoxazoles 4 by the condensation of 2-aminophenol 1 and benzoyl chlorides 2 under microwave irradiation in solvent free reaction conditions. the advantages of this methodology are good product yields (60-98%), being environmentally benign, short reaction times and easy work up.

Some aryl and heteroaryl azido compounds were synthesized from the reaction of corresponding fluoro and chloro compounds with sodium azide in DMF as solvent and under various reaction conditions especially ultrasonic irradiation. Reaction of aromatic and heteroaromatic azido compound with thioacetic acid in the presence of sodium hydrogen carbonate and in methanol as solvent led to the differen...

An eco-safe and facile multi-component domino reaction has been described for the synthesis of 1H-pyrazolo [1, 2-b] phthalazine-5, 10-dione derivatives. The products were obtained by a four-component condensation reaction between phthalimide, hydrazine monohydrate, aromatic aldehyde derivatives and malononitrile in the presence of a catalytic amount of copper (II) oxide (CuO) ...

Silica-bonded n-propyltriethylene-tetramine (SBNPTT) was found as an efficient solid base for the synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromenes. Chromene derivatives were obtained via the three-component condensation reaction of aromatic aldehydes, malononitrile, and dimedone at 80 oC under solvent-free conditions. The heterogeneous solid base showed much the same efficiency when u...

an efficient synthesis route to 1,4-dihydropyrimidine derivatives from reaction of divergent aldehydes with ethylacetoacetate and urea under solvent-free conditions by zno nanoparticles as a relative in expansive, eco-friendly, easy available, non-volatile, non-explosion, thermally robust, recyclable and easy to handle catalyst at 90°c with excellent yields is described. unenhanced reaction tim...

Silica-bonded n-propyltriethylene-tetramine (SBNPTT) was found as an efficient solid base for the synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromenes. Chromene derivatives were obtained via the three-component condensation reaction of aromatic aldehydes, malononitrile, and dimedone at 80 oC under solvent-free conditions. The heterogeneous solid base showed much the same efficiency when u...