2,5-Bis-tri:bromo:methyl-1,3,4-thiadiazole prepn. - by brominating 2,5-di:methyl-1,3,4-thiazole in organic acid, useful as e.g. flame retardant for polystyrene(s)

摘要

(I) is made by brominating 2,5-dimethyl-1,3,4-thiadiazole in the presence of an organic acid. (I) is useful as a flame retardant additive in styrene polymers; as an adhesion promoter; as an intermediate in the prodn. of dyes; and as a phosphorescent marking agent for plastics. The process gives high yields of (I), largely free from dark coloured highly brominated by-prods. which have a deleterious effect on the flame retardant properties of the compsn.