On the Mechanism of the Caro Synthesis of Methylene Blue
Francisco Sánchez‐Viesca, Reina Gómez
Abstract
The recent interest for new applications of methylene blue as a promising drug for several important ailments prompted us to fill unknown aspects related to this compound. Since there is no mechanism on the Caro synthesis of methylene blue, we provide the electron flow, step by step, from the starting N,N-dimethylphenylenediamine to the dibenzothiazine derivative. It is a free radical generation system due to the oxidizing properties of ferric chloride. We pointed out the alternative reactions that take place with hydrogen sulphide, the reducer from which the thiazine ring is formed.
Topics & Concepts
MethyleneOxidizing agentMethylene blueChemistryRing (chemistry)ThiazineChlorideFerricCombinatorial chemistryMechanism (biology)PhotochemistryOrganic chemistryCatalysisPhilosophyEpistemologyPhotocatalysisSynthesis and Biological EvaluationSynthesis and Reactions of Organic CompoundsRadical Photochemical Reactions