title: Mechanistic insights into ring-opening and decarboxylation of 2-pyrones in liquid water and tetrahydrofuran.
abstract: 2-Pyrones, such as triacetic acid lactone, are a promising class of biorenewable platform chemicals that provide access to an array of chemical products and intermediates. We illustrate through the combination of results from experimental studies and first-principle density functional theory calculations that key structural features dictate the mechanisms underlying ring-opening and decarboxylation of 2-pyrones, including the degree of ring saturation, the presence of C═C bonds at the C4═C5 or C5═C6 positions within the ring, as well as the presence of a β-keto group at the C4 position. Our results demonstrate that 2-pyrones undergo a range of reactions unique to their structure, such as retro-Diels-Alder reactions and nucleophilic addition of water. In addition, the reactivity of 2-pyrones and the final products formed is shown to depend on the solvent used and the acidity of the reaction environment. The mechanistic insights obtained here provide guidance for the selective conversion of 2-pyrones to targeted chemicals.
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, Wisconsin 53706, USA.
authors.forename: Mei
authors.initials: M
authors.lastname: Chia
authors.forename: M Ali
authors.initials: MA
authors.lastname: Haider
authors.forename: Gerald
authors.initials: G
authors.lastname: Pollock
authors.forename: George A
authors.initials: GA
authors.lastname: Kraus
authors.forename: Matthew
authors.initials: M
authors.lastname: Neurock
authors.forename: James A
authors.initials: JA
authors.lastname: Dumesic
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D005663:Furans / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D011753:Pyrones / Q000737:chemistry*; D011789:Quantum Theory; D014867:Water / Q000737:chemistry*
chemical_list: D002264:Carboxylic Acids; D005663:Furans; D011753:Pyrones; D014867:Water; C018674:tetrahydrofuran