p-TOLUENESULFONIC ACID-CATALYZED EFFICIENT SYNTHESIS OF DIHYDROPYRIMIDINES: IMPROVED HIGH YIELDING PROTOCOL FOR THE BIGINELLI REACTION

ABSTRACT Dihydropyrimidines are prepared by a one-pot cyclocondensation of aldehydes, β-ketoesters and urea with p-toluenesulfonic acid-catalyzed condensation reaction. Yields are significantly higher than utilizing classical Biginelli reaction conditions.

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