Abstract

NOVEL AND EFFICIENT YALO3: EU3+ NANO CATALYST FOR THE SYNTHESIS OF 3, 4-DIHYDROPYRIMIDIN-2(1H)-ONES/-THIONES

K. R. Gopinath, H. B. Premkumar, H. S. Shekar, K. J. Rajendraprasad,
H. Nagabhushana and Manjula Krishnappa*

ABSTRACT

Europium activated YAlO3 nano catalyst as prepared by low-temperature solution combustion synthesis. The as-prepared precursor oxide powder was calcined (1000°C, 3h) in oxygen atmosphere to get crystalline product. Powder X-ray diffraction (PXRD) studies on doped and un-doped YAlO3 samples show monoclinic phase without any impurities and also reveals incorporation of Eu3+ in the YAlO3 lattice. Transmission electron microscopy (TEM) confirms the nano-dimension of the product with size in the range 30–100 nm. Photoluminescence (PL) studies on europium activated YAlO3 show an intense peak at 611nm, which is due to 5D0  7F2 transition of Eu3+ ions. A well characterized YAlO3: Eu3+ nano powder was used in synthesis of a series of 3,4-dihydropyrimidin-2(1H)-ones/-thiones via condensation of ethyl acetoacetate, substituted arylaldehydes and urea or thiourea in ethanol heated at 80oC in the presence of Nano-YAl2O3: Eu+ catalyst displayed an excellent catalytic property and the reaction completed within 1.5 hrs with high yield (82−92%). This new nano catalyst has several advantages like higher yield, lower cost, reduced environmental hazards; this is very convenient protocol for scale up reaction.

Keywords: Nano-YAl2O3:Eu3+, 3, 4-dihydropyrimidin-2(1H)-ones (DHPMs), Multi component reactions, ecofriendly.