Hydrodefluorination of functionalized fluoroaromatics with triethylphosphine: A theoretical and experimental study
Por:
Facundo A.A., Arévalo A., Fundora-Galano G., Flores-Álamo M., Orgaz E., García J.J.
Publicada:
1 ene 2019
Resumen:
Recently we reported the metal free hydrodefluorination of selected fluoroaromatics using triethylphosphine as the sole defluorinating agent. That prompted us to evaluate the mechanistic proposal and in the light of these results, along with new experimental evidence, we have now modified the initial proposal. The new mechanism avoids the highly energetic ß-elimination step of roughly 71 kcal mol -1 for hexafluorobenzene and pentafluoropyridine at 393.15 K, invoking the participation of water. The use of D 2 O confirmed the role of water as the hydrogen source, yielding the corresponding deutero-defluorinated products; DFT calculations agree with this new proposed mechanism. We also report herein the use of this one-pot hydrodefluorination method applied to a broader number of fluoroaromatic derivatives; some of them allowed the collection of key mechanistic evidence. © 2019 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Filiaciones:
Facundo A.A.:
Facultad de Química, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Fac Quim, Ciudad Univ, Mexico City 04510, DF, Mexico
Arévalo A.:
Facultad de Química, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Fac Quim, Ciudad Univ, Mexico City 04510, DF, Mexico
Fundora-Galano G.:
Facultad de Química, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Fac Quim, Ciudad Univ, Mexico City 04510, DF, Mexico
Flores-Álamo M.:
Facultad de Química, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Fac Quim, Ciudad Univ, Mexico City 04510, DF, Mexico
Orgaz E.:
Facultad de Química, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Fac Quim, Ciudad Univ, Mexico City 04510, DF, Mexico
García J.J.:
Facultad de Química, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Fac Quim, Ciudad Univ, Mexico City 04510, DF, Mexico
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