title: One-Pot Selective Catalytic Synthesis of Pyrrolidone Derivatives from Ethyl Levulinate and Nitro Compounds.
abstract: N-substituted 5-methyl-2-pyrrolidones were prepared in a one-pot process starting from ethyl levulinate and nitro compounds in the presence of a nanosized Pt-based catalyst. Pt supported on TiO2nanotubes (Pt/TiO2-NT) catalyzed the synthesis of N-substituted 5-methyl-2-pyrrolidones through a cascade process involving the reduction of nitro compounds, formation of the intermediary imine, hydrogenation, and subsequent cyclization. A bifunctional metal-acid system was a suitable catalyst for the process. Pt supported on TiO2showed lower catalytic activity than Pt/TiO2-NT owing to the strong adsorption of nitro compounds during the first reaction step that poisoned the acidic sites and strongly decreased the rate of amination and cyclization. However, Pt/TiO2-NT with milder acid sites was less affected by the adsorption of nitro compounds and the full cascade process could proceed. The results indicate that the prepared Pt/TiO2-NT is a chemoselective and reusable catalyst that can be applied to the synthesis of a variety of N-substituted 5-methyl-2-pyrrolidones starting from nitro compounds with excellent yields in absence of an additional organic solvent under mild reaction conditions.
authors.affiliation: Instituto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Avda dels Tarongers s/n, 46022, Valencia, Spain.
authors.forename: Juan D
authors.identifier: http://orcid.org/0000-0002-6862-6443
authors.initials: JD
authors.lastname: Vidal
authors.affiliation: Instituto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Avda dels Tarongers s/n, 46022, Valencia, Spain.
authors.forename: Maria J
authors.identifier: http://orcid.org/0000-0002-3575-2902
authors.initials: MJ
authors.lastname: Climent
authors.affiliation: Instituto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Avda dels Tarongers s/n, 46022, Valencia, Spain.
authors.forename: Avelino
authors.identifier: http://orcid.org/0000-0002-2232-3527
authors.initials: A
authors.lastname: Corma
authors.affiliation: Instituto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Avda dels Tarongers s/n, 46022, Valencia, Spain.
authors.forename: Dr Patricia
authors.initials: DP
authors.lastname: Concepcion
authors.affiliation: Instituto de Tecnología Química (UPV-CSIC), Universitat Politècnica de València, Avda dels Tarongers s/n, 46022, Valencia, Spain.
authors.forename: Sara
authors.identifier: http://orcid.org/0000-0003-1758-5095
authors.initials: S
authors.lastname: Iborra
mesh_terms: D000327:Adsorption; D002384:Catalysis; D060326:Chemistry Techniques, Synthetic; D006865:Hydrogenation; D007982:Levulinic Acids / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry; D009574:Nitro Compounds / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry; D011760:Pyrrolidinones / Q000138:chemical synthesis* / Q000737:chemistry*; D013379:Substrate Specificity; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D007982:Levulinic Acids; D009574:Nitro Compounds; D011760:Pyrrolidinones; C009495:titanium dioxide; D010984:Platinum; C542586:ethyl levulinate; D014025:Titanium
keywords: ethyl levulinate; nitro compounds; platinum; pyrrolidones; reductive amination