Atribución-NoComercial-SinDerivadas 4.0 InternacionalNieto Gómez, Carla IsabelCornago, María del PilarCabildo, María del PilarSanz del Castillo, DionisiaClaramunt Vallespí, Rosa MaríaElguero, José2024-08-282024-08-282019-03Nieto, C. I., Cornago, M. P., Cabildo, M. P., Sanz, D., Claramunt, R. M., Torralba, M. C., & Elguero, J. (2019). Synthesis, structure and NMR study of fluorinated isoxazoles derived from hemi-curcuminoids. Journal of Fluorine Chemistry, 219, 39-49. https://doi.org/10.1016/J.JFLUCHEM.2018.12.0120022-1139https://doi.org/10.1016/j.jfluchem.2018.12.012https://hdl.handle.net/20.500.14468/23575This is an Accepted Manuscript of an article published in “Journal of Fluorine Chemistry, 219, 39-49", is available online at the publisher's website: Elsevier, https://doi.org/10.1016/j.jfluchem.2018.12.012Este es el manuscrito aceptado del artículo publicado en “Journal of Fluorine Chemistry, 219, 39-49", disponible en línea en el sitio web del editor: Elsevier, https://doi.org/10.1016/j.jfluchem.2018.12.012The purpose of this work is to prepare a series of isoxazoles bearing phenyl and 4'-hydroxy-styryl substituents at position 3 and 5; besides the phenyl group of the styryl residue bears one or two fluorine substituents. They were prepared to study their structure in the solid state and in solution by X-ray crystallography and solid-state NMR (SSNMR) for the solid state and NMR for the solution. The reaction of hydroxylamine with hemi-curcuminoid β-diketones affords two isomeric isoxazoles we have named series a (3-phenyl) and b (5-phenyl) that have been identified and characterized. Four pairs have been prepared that in three cases bear one or two fluorine atoms. Three X-ray structures have been determined 3a, 3b and 5b; 3a crystallizes without solvent, 3b crystallizes with a water molecule hydrogen-bonded to a phenolic OH, finally 5b crystallizes as a solvate with a methanol molecule hydrogen-bonded to the isoxazole N atom. This hydrogen bond results in larger differences between 15N chemical shifts in DMSO-d6 solution and in the solid state. The splitting of some signals observed in Cross-Polarization Magic Angle Spinning (CPMAS) 13C NMR was assigned to 1JCF dipolar couplings. The combined use of crystallography and SSNMR affords a complete characterization of isomeric isoxazoles, in particular the assignment of an isoxazole to a or to b series is not a trivial matter. In this work, we describe methods for the synthesis of isoxazoles bearing fluorine substituents that are promising structures for drug discovery.eninfo:eu-repo/semantics/openAccess23 Química::2306 Química orgánicaartículoIsoxazoleHemi-curcuminoidsFluorinated isoxazolesSolid-state NMRX-ray crystallography