Flow reactor approach for the facile and continuous synthesis of efficient Pd@Pt core-shell nanoparticles for acceptorless dehydrogenative synthesis of pyrimidines from alcohols and amidines

Carbon supported Pd@Pt core-shell nanoparticles catalyst was prepared in a flow reactor toachieve enhanced catalytic activities with low Pt loading for the acceptorless dehydrogenative synthesis of pyrimidines. Spectroscopic (XAS analysis) and microscopic (HAADF-STEM) techniques reveled that the core-shell structure was formed by the applied preparation method. The Pd@Pt/PVP (polyvinylpyrrolidone)/C catalyst showed the activity for the three component one pot synthesis of pyrimidines through a series of consecutive reactions including oxidation of alcohols, C?C, and C?N coupling, followed by heterocyclization and dehydrogenation employing various primary alcohols, secondary alcohols, and amidines. The reaction mechanism on Pd@Pt/ PVP/C catalyst was explored by comparison with the control experiments.