title: An efficient synthesis of pyridoxal oxime derivatives under microwave irradiation.
abstract: Quaternary salts of pyridoxal oxime have been synthesized by the quaternization of pyridoxal oxime with substituted phenacyl bromides using microwave heating. Microwave-assisted rapid synthesis was done both in solvent (acetone) and under solvent-free conditions. Good to excellent yields (58%-94%) were obtained in acetone in very short reaction times (3-5 min) as well as in the solvent-free procedure (42%-78%) in very short reaction times (7-10 min) too. Effective metodologies for the preparation of pyridoxal oxime quaternary salts, having the advantagies of being eco-friendly, easy to handle, and performed in shorter reactions time are presented. The structure of compound 7, in which a 4-fluorophenacyl moiety is bonded to the pyridinium ring nitrogen atom, was unequivocally confirmed by the single-crystal X-ray diffraction method.
authors.affiliation: Josip Juraj Strossmayer University of Osijek, Faculty of Food Technology Osijek, Kuhačeva 20, 31000 Osijek, Croatia. valentina.busic@ptfos.hr.
authors.forename: Dajana
authors.initials: D
authors.lastname: Gašo-Sokač
authors.affiliation: Josip Juraj Strossmayer University of Osijek, Faculty of Food Technology Osijek, Kuhačeva 20, 31000 Osijek, Croatia. valentina.busic@ptfos.hr.
authors.forename: Valentina
authors.initials: V
authors.lastname: Bušić
authors.affiliation: University of Zagreb, Faculty of Textile Technology, Department of Applied Chemistry, Prilaz baruna Filipovića 28a, 10000 Zagreb, Croatia. mario.cetina@ttf.hr.
authors.forename: Mario
authors.initials: M
authors.lastname: Cetina
authors.affiliation: Faculty of Food Technology and Biotechnology, Department of Chemistry and Biochemistry, Pierottijeva 6, 10000 Zagreb, Croatia. mjukic@pbf.hr.
authors.forename: Marijana
authors.initials: M
authors.lastname: Jukić
mesh_terms: D000098:Acetophenones / Q000737:chemistry*; D008872:Microwaves; D015394:Molecular Structure; D011730:Pyridoxal / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000098:Acetophenones; D011730:Pyridoxal; C028073:pyridoxaloxime; C013190:phenacyl bromide