2-(Fluoro-) and 2-(methoxyanilino)-1,4-naphthoquinones. Synthesis and mechanism and effect of fluorine substitution on redox reactivity and NMR

Authors

Elisa Leyva, Universidad Autonoma de San Luis Potosi
Kim M. Baines, The University of Western OntarioFollow
Claudia G. Espinosa-González, Universidad Autonoma de San Luis Potosi
Diego A. Magaldi-Lara, Universidad Autonoma de San Luis Potosi
Silvia E. Loredo-Carrillo, Universidad Autonoma de San Luis Potosi
Telma A. De Luna-Méndez, Universidad Autonoma de San Luis Potosi
Lluvia I. López, Universidad Autonoma de Coahuila

Document Type

Article

Publication Date

12-1-2015

Journal

Journal of Fluorine Chemistry

Volume

180

First Page

152

Last Page

160

URL with Digital Object Identifier

10.1016/j.jfluchem.2015.08.016

Abstract

The influence of catalysts on the addition of methoxy- and fluoroanilines with 1,4-naphthoquinone to give methoxy- and fluoro-substituted 2-(anilino)-1,4-naphthoquinones was investigated. In the absence of a catalyst, this reaction requires long times and low yields of the anilino derivatives are obtained accompanied with the formation of several secondary products. Excellent yields were obtained with a catalytic amount of a Lewis acid with strong oxidation properties such as CeCl3 or FeCl3. Excellent yields were also obtained when the reaction was performed with a Brønsted acid/oxidant mixture such as AcOH/Cu(OAc)2. This addition reaction was also investigated using microwave irradiation. A discussion on reaction conditions and mechanism is presented. The ¹H and ¹³C NMR data of all the derivatives were analyzed and assigned using two dimensional ¹H-¹³C gHSQC and gHMBC NMR experiments. The effect of fluorine substitution on redox and NMR properties was also investigated.