silica-bonded n-propyldiethylenetriamine sulfamic acid (sbpdsa) was found as an efficient solid acid for the synthesis of coumarins. coumarin derivatives were obtained via the pechmann condensation reaction of phenols and β-keto-esters at 80 oc under solvent-free conditions. also, biscoumarins were obtained via the condensation of aldehydes and 4-hydroxycoumarin in water at reflux conditions. t...

Friedel–Crafts synthesis of triarylmethanes over 3-methyl-1-sulfonic acid imidazolium tetrachloroaluminate under green conditions:In this work, Friedel–Crafts (FC) alkylation of various arenes with aromatic aldehydes catalyzed by 3-methyl-1-sulfonic acid imidazoliumtetrachloroaluminate {[Msim]AlCl4}, as a green catalyst, to prepare triarylmethanes (TAMs) has been carried out. Some aromatic alde...

Highly substituted 1,4-dihydropyrano[2,3-c]pyrazole derivatives were synthesized by four-component reaction of aromatic aldehydes, malononitrile, ethyl acetoacetate and various phenylhydrazine, using nickel ferrite as a recyclable nanocatalyst by a grinding method under solvent-free and thermal conditions. The reaction has the advantages of good yields, less pollution, ease of separation of the...

This study introduces a green and efficient method for preparation of biologically-active substituted 4H-pyrans using the one-pot three-component reaction of aromatic aldehydes, dimedone and malononitrile in the presence of cobalt oxide nanoparticles. Co3O4 nanoparticles were used as an efficient catalyst for the synthesis of polyhydroquinoline derivatives by the reaction ...

BACKGROUND Interleukin-8 (IL-8) functions as a major chemoattractant and plays pivotal roles in the initiation and development of chronic obstructive pulmonary disease (COPD), and tobacco smoke is a most risk factor contributing to the development of COPD. Hence, we have screened some of the tobacco smoke-derived chemical compounds that potentially induce the production of IL-8 in human bronchi...

Reductive aminationa varietyof aldehydes with different anilines has been performed byZn(BH4)2/ MgBr2as reducing system in THF at room temperature in high to excellent yields of the corresponding secondary amines (80-90%).

Aromatic aldehydes are efficiently condensed with 2'-hydroxyacetophenone by polymer-supported basic ionic liquid as an excellent heterogeneous catalyst utilizing the Claisen–Schmidt reaction. Microwave irradiation has been employed, providing flavanone in good yield and short reaction time.