Manganese-Containing Periodic Mesoporous Organosilica with Ionic-Liquid Framework (Mn@PMO-IL): A Powerful, Durable, and Reusable Nanocatalyst for the Biginelli Reaction

The catalytic application of a novel manganese-containing periodic mesoporous organosilica with ionic-liquid framework (Mn@PMO-IL) in the Biginelli reaction was investigated. First, the Mn@PMO-IL nanocatalyst was prepared and characterized by TEM, SEM, X-ray photoelectron spectroscopy, and nitrogen-sorption analysis. The catalyst was then used in the one-pot Biginelli condensation of various aldehydes with urea and alkyl acetoacetates under solvent-free conditions. The corresponding dihydropyrimidone products were obtained in high to excellent yields and selectivities at short reaction times. Moreover, the catalyst was recovered and successfully reused many times with no notable decrease in activity and selectivity.