title: Combined experimental and computational studies on the physical and chemical properties of the renewable amide, 3-acetamido-5-acetylfuran.
abstract: The pK(a) of 3-acetamido-5-acetylfuran (3A5AF) was predicted to be in the range 18.5-21.5 by using the B3LYP/6-311+G(2d,p) method and several amides as references. The experimental pK(a) value, 20.7, was determined through UV/Vis titrations. Its solubility was measured in methanol-modified supercritical CO2 (mole fraction, 3.23×10(-4), cloud points 40-80 °C) and it was shown to be less soluble than 5-hydroxymethylfurfural (5-HMF). Dimerization energies were calculated for 3A5AF and 5-HMF to compare hydrogen bonding, as such interactions will affect their solubility. Infrared and (1) H nuclear magnetic resonance spectra of 3A5AF samples support the existence of intermolecular hydrogen bonding. The highest occupied molecular orbital, lowest unoccupied molecular orbital, and electrostatic potential of 3A5AF were determined through molecular orbital calculations using B3LYP/6-311+G(2d,p). The π-π* transition energy (time-dependent density functional theory study) was compared with UV/Vis data. Calculated atomic charges were used in an attempt to predict the reactivity of 3A5AF. A reaction between 3A5AF and CH3MgBr was conducted. As 3A5AF is a recently developed renewable compound that has previously not been studied extensively, these studies will be helpful in designing future reactions and processes involving this molecule.
authors.affiliation: Department of Chemistry, Memorial University, St. John's, NL, A1C 5S7 (Canada).
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Rowley
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Kerton
mesh_terms: D000081:Acetamides / Q000737:chemistry*; D000117:Acetylglucosamine / Q000737:chemistry; D019281:Dimerization; D005662:Furaldehyde / Q000031:analogs & derivatives / Q000737:chemistry; D005663:Furans / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D012995:Solubility; D055672:Static Electricity; D013816:Thermodynamics
chemical_list: D000081:Acetamides; D005663:Furans; C008046:5-hydroxymethylfurfural; D005662:Furaldehyde; C039669:2-acetylfuran; D000117:Acetylglucosamine
keywords: acidity; density functional calculations; hydrogen bonds; renewable resources; solubility