title: Synthesis of bio-based methacrylic acid by decarboxylation of itaconic acid and citric acid catalyzed by solid transition-metal catalysts.
abstract: Methacrylic acid, an important monomer for the plastics industry, was obtained in high selectivity (up to 84%) by the decarboxylation of itaconic acid using heterogeneous catalysts based on Pd, Pt and Ru. The reaction takes place in water at 200-250 °C without any external added pressure, conditions significantly milder than those described previously for the same conversion with better yield and selectivity. A comprehensive study of the reaction parameters has been performed, and the isolation of methacrylic acid was achieved in 50% yield. The decarboxylation procedure is also applicable to citric acid, a more widely available bio-based feedstock, and leads to the production of methacrylic acid in one pot in 41% selectivity. Aconitic acid, the intermediate compound in the pathway from citric acid to itaconic acid was also used successfully as a substrate.
authors.affiliation: Chair of Biobased Commodity Chemistry, Wageningen University & Research Centre, P.O. Box 17, 6700AA Wageningen (The Netherlands), Fax: (+31) 317-483011.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Le Nôtre
authors.forename: Susan C M
authors.initials: SC
authors.lastname: Witte-van Dijk
authors.forename: Jacco
authors.initials: J
authors.lastname: van Haveren
authors.forename: Elinor L
authors.initials: EL
authors.lastname: Scott
authors.forename: Johan P M
authors.initials: JP
authors.lastname: Sanders
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry; D002244:Carbon / Q000737:chemistry; D002384:Catalysis; D060326:Chemistry Techniques, Synthetic; D019343:Citric Acid / Q000737:chemistry*; D003653:Decarboxylation; D008689:Methacrylates / Q000138:chemical synthesis* / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry; D011312:Pressure; D012428:Ruthenium / Q000737:chemistry; D013386:Succinates / Q000737:chemistry*; D013696:Temperature; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D008689:Methacrylates; D013386:Succinates; D028561:Transition Elements; C008384:methacrylic acid; D019343:Citric Acid; D010165:Palladium; D002244:Carbon; D012428:Ruthenium; D000537:Aluminum Oxide; C005229:itaconic acid
keywords: biomass; heterogeneous catalysis; palladium; platinum; polymers