Efficient electrosynthesis of 1,2,4-triazino[3,4-b]-1,3,4-thiadiazine derivatives

Electrochemical oxidation of catechols 1a-d has been studied in the presence of 4-amino-6-methyl-1,2,4-triazine-3-thion-5-one 3 as a nucleophile in aqueous solutions, using cyclic voltammetry and controlled-potential coulometry, leading to the efficient synthesis of 1,2,4-triazino[3,4-b]-1,3,4-thiadiazines.