One pot multicoponent synthesis of 4-hydroxy-6-methyl-3-(3 phenylthiazolo [2,3<em>c</em>][1,2,4]triazol-5-yl)-2<em>H</em>-pyran-2-ones

960-964An efficient one pot multicomponent reaction for the synthesis of 4-hydroxy-6-methyl-3-(3-phenylthiazolo[2,3-c][1,2,4]triazol-5-yl)-2H-pyran-2-ones with good to excellent yields have been described. Reaction of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one 1, thiosemicarbazide 2 and various aromatic carboxylic acids 3a-j in dry toluene and POCl3 afford 4-hydroxy-6-methyl-3-(3-phenylthiazolo[2,3-c][1,2,4]triazol-5-yl)-2H-pyran-2-ones. All the synthesized compounds have been characterized from their analytical and spectral data

Novel one-pot expeditious synthesis of 2,4-disubstituted thiazoles through a three-component reaction under solvent free conditions

<p>An expeditious one pot method has been developed for the synthesis of 2,4-disubstituted thiazoles under solvent free conditions via a multicomponent approach. Substituted thiazoles were synthesized with high yields by the reaction of cyclic ketones, thiosemicarbazide, and phenacyl bromides or 3-(2-bromoacetyl)-2<i>H</i>-chromen-2-ones in a shorter reaction time with high purity via simple purification technique.</p

One pot multicoponent synthesis of 4-hydroxy-6-methyl-3-(3-phenylthiazolo [2,3<em>c</em>][1,2,4]triazol-5-yl)-2<em>H</em>-pyran-2-ones

1089-1093An efficient one pot multicomponent reaction for the synthesis of 4-hydroxy-6-methyl-3-(3-phenylthiazolo[2,3-c][1,2,4]triazol-5-yl)-2H-pyran-2-ones with good to excellent yields has been described. Reaction of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one (1), thiosemicarbazide (2) and various aromatic carboxylic acids (3a-j) in dry toluene and POCl3 affords 4-hydroxy-6-methyl-3-(3-phenylthiazolo[2,3-c][1,2,4]triazol-5-yl)-2H-pyran-2-ones. All the synthesized compounds have been characterized by their analytical and spectral data

Recyclable Bi2WO6-nanoparticle mediated One-pot multicomponent reactions in aqueous medium at room temperature

Different types of multicomponent reactions (MCRs) are reported using Bi2O3, BiVO4, and Bi2WO6 (nanoparticle) as heterogeneous catalysts. Among these, Bi2WO6 nano particles showed excellent reactivity for the synthesis of functionalized dihydropyridine, polyhydroquinoline, 4H-chromene and 2-amino-4H-benzo[b]pyran derivatives at ambient temperature in aqueous medium. All the reactions gave good to excellent yields in 10-45 minutes in the presence of 5 mol% (optimized) of the catalyst. The catalyst was regenerated and reused up to 5 cycles without losing catalytic activity. The gram scale synthesis of dihydropyridine gave the desired product in 82 % yield in 2 h.by Banoth Paplal, S. Nagaraju, Palakollu Veerabhadraiah, Kodam Sujatha, Sriram Kanvah, B. Vijaya Kumar and Dhurke Kashinat