Sodium fluoride as an efficient catalyst for the synthesis of 2,4-disubstituted-1,3-thiazoles and selenazoles at ambient temperature

Sodium fluoride was found to be a simple, mild and efficient catalyst for the synthesis of 2,4- disuhstituted 1,3-thiazoles and selenazoles utilizing phenacyl bromides/3-（2-bromoacetyl）-2H-chro- men-2-one and thioureaJphenylthiourea/selenourea in aqueous methanol at ambient temperature. Analytically pure products are formed within 1-3 rain in excellent yields.

1-Sulfopyridinium chloride:Green and expeditious ionic liquid for the one-pot synthesis of fused 3,4-dihydropyrimidin-2(1H)-ones and thiones under solvent-free conditions

1-Sulfopyridinium chloride portrayed as an efficient and recyclable ionic liquid for the synthesis of fused3,4-dihydropyrimidin-2（1H）-ones and thiones via a modified Biginelli reaction involving one-pot three component condensation of 6-methoxy-1-tetralone,arylaldehydes and urea/thiourea under solventfree conditions.Analytically pure products are formed within 10–20 min in excellent yields.