Barium 5-(tert-butyl)-2,3-dihydroxybenzenesulfonate

Lyubov G Rubicheva,Daniil A Lukyanov

doi:10.3390/m1336

Abstract

Catechols and their derivatives attract great scientific interest due to the broad spectrum of their functional properties, including complexation, redox behavior, association ability and antioxidant activity. Because of the low molecular mass and two-electron redox process, they are considered to be a promising energy storage compound in different types of electrochemical power sources, such as metal-ion batteries or redox flow batteries. Herein, we report a preparation of the sterically hindered sulfonated catechol, namely the barium salt of 5-(tert-butyl)-2,3-dihydroxybenzenesulfonic acid, by the direct sulfonation of 4-tert-butylcatechol, by concentrated sulfuric acid. The proposed procedure is green and atom-economic, providing the desired product in high yield after simple purification. The solvent-free procedure is inexpensive and highly scalable, which enables direct industrial production of the title product. The resulting product was characterized by the 1H and 13C nuclear magnetic resonance (NMR) and ESI-high resolution mass spectrometry (ESI-HRMS).

Highlights

Natural and synthetic polymeric catechols meet their application as cathode materials or binders in accumulators [7,8] and supercapacitors [9,10], while the molecular catechols, for example, 3,5-pyrocatecholdisulfonate (Tiron), are considered as promising catholytes for organic flow batteries [11]
We attempted to prepare the desired product by the sulfonation of the 4-tertFirst, we attempted prepare desired we product by the sulfonation of the 4-tertbutylcatechol with the chlorosulfonic acid,tousing the the procedure described earlier for butylcatechol with the chlorosulfonic acid, using the procedure we described earlier for the the sulfonation of the polycatechol [14]
Treatment of the 4-tert-butylcatechol with the 80% sulfuric acid, analogous to the proceof the 4-tert-butylcatechol with the 80% sulfuric acid, analogous to the procedure described dure described in the literature [13], left the starting material intact

Summary

Introduction

Natural and synthetic polymeric catechols meet their application as cathode materials or binders in accumulators [7,8] and supercapacitors [9,10], while the molecular catechols, for example, 3,5-pyrocatecholdisulfonate (Tiron), are considered as promising catholytes for organic flow batteries [11]. The novel sterically hindered sulfonated catechol may be useful for the development of the redox flow batteries or as a model compound for the investigation of polymeric sulfocatechol materials for energy storage. In case of the sulfonation of tert-butyl catechol with strongly acidic agents, the acid-promoted cleavage of the tert-butyl group is possible. Another issue was how to purify the resulting sulfonic acid from the inorganic salts.

Results

Reaction conditionsoffor sulfonation of thewith

J shows

General Consideration