AUTHOR=Rodríguez-Padrón Daily , Puente-Santiago Alain R. , Balu Alina M. , Muñoz-Batista Mario J. , Luque Rafael 

TITLE=Continuous Flow Synthesis of High Valuable N-Heterocycles via Catalytic Conversion of Levulinic Acid

JOURNAL=Frontiers in Chemistry

VOLUME=7

YEAR=2019

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2019.00103

DOI=10.3389/fchem.2019.00103

ISSN=2296-2646

ABSTRACT=<p>Graphitic carbon nitride (g-C<sub>3</sub>N<sub>4</sub>) was successfully functionalized with a low platinum loading to give rise to an effective and stable catalytic material. The synthesized g-C<sub>3</sub>N<sub>4</sub>/Pt was fully characterized by XRD, N<sub>2</sub> physisorption, XPS, SEM-Mapping, and TEM techniques. Remarkably, XPS analysis revealed that Pt was in a dominant metallic state. In addition, XPS together with XRD and N<sub>2</sub> physisorption measurements indicated that the g-C<sub>3</sub>N<sub>4</sub> preserves its native structure after the platinum deposition process. g-C<sub>3</sub>N<sub>4</sub>/Pt was applied to the catalytic conversion of levulinic acid to N-heterocycles under continuous flow conditions. Reaction parameters (temperature, pressure, and concentration of levulinic acid) were studied using 3 levels for each parameter, and the best conditions were employed for the analysis of the catalyst's stability. The catalytic system displayed high selectivity to 1-ethyl-5-methylpyrrolidin-2-one and outstanding stability after 3 h of reaction.</p>