title: Tautomeric equilibria of 3-formylacetylacetone: low-temperature NMR spectroscopy and ab initio calculations.
abstract: Keto-enol tautomerization of 3-formylacetylacetone has been studied by NMR spectroscopy, ab initio, and DFT calculations in the gas phase and continuum solvation. By employing very low temperatures in a freonic solvent, tautomeric and conformational equilibria in the slow exchange regime were analyzed in detail. The beta-tricarbonyl compound always adopts a structure with an enolized keto group irrespective of an increasing dielectric constant of the solvent when lowering the temperature of the Freon mixture. This experimentally observed tautomeric distribution of 3-formylacetylacetone is correctly reproduced by continuum solvated DFT calculations.
authors.affiliation: Institut für Chemie, Freie Universität Berlin, Takustrasse 3, D-14195 Berlin, Germany.
authors.forename: Eline M
authors.initials: EM
authors.lastname: Basílio Janke
authors.forename: Sebastian
authors.initials: S
authors.lastname: Schlund
authors.forename: Alexander
authors.initials: A
authors.lastname: Paasche
authors.forename: Bernd
authors.initials: B
authors.lastname: Engels
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Dede
authors.forename: Ibrar
authors.initials: I
authors.lastname: Hussain
authors.forename: Peter
authors.initials: P
authors.lastname: Langer
authors.forename: Michael
authors.initials: M
authors.lastname: Rettig
authors.forename: Klaus
authors.initials: K
authors.lastname: Weisz
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D003500:Cyclization; D005561:Formates / Q000737:chemistry*; D005740:Gases; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008958:Models, Molecular; D010422:Pentanones / Q000737:chemistry*; D012996:Solutions; D012997:Solvents; D013237:Stereoisomerism; D013696:Temperature
chemical_list: C544636:3-formylacetylacetone; D000447:Aldehydes; D005561:Formates; D005740:Gases; D010422:Pentanones; D012996:Solutions; D012997:Solvents