title: Ultrasonic-assisted preparation of nano eggshell powder: a novel catalyst in green and high efficient synthesis of 2-aminochromenes.
abstract: The nano eggshell powder (NESP) has been prepared by ultrasound irradiation and used as a novel and biodegradable catalyst with high catalytic activity and reusability in green synthesis of 2-aminochromenes via condensation of α- or β-phathol, malononitrile and aromatic aldehydes at 120 °C under solvent-free conditions. The reaction proceeds to completion within 10-35 min in 91-98% yield. Nano eggshell catalyst was characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and X-ray fluorescence, thermal gravimetric, surface area and elemental analyses. In addition, the catalytic activity and chemical structure of nano-sized eggshell were compared with pure CaCO3.
authors.affiliation: Department of New Materials, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, P.O. Box 76315-117, Kerman, Iran. emosaddegh@gmail.com
authors.forename: Elaheh
authors.initials: E
authors.lastname: Mosaddegh
mesh_terms: D000818:Animals; D001578:Benzopyrans / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D004528:Egg Shell / Q000737:chemistry*; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D014465:Ultrasonics
chemical_list: D001578:Benzopyrans