On the formation of 2,3,4,6‐tetrabromopyridine during the bromination of 2,6‐dibromopyridine at about 500°: (43th Communication on derivatives of pyridine and quinoline.)

The bromination of 2,6-dibromopyridine in the gaseous phase and in the presence of pumice as a contact substance has been reinvestigated in the temperature range of 500-580°; besides 2,4,6-tribromopyridine, which is the main product of the reaction as already found by den Hertog and Wibaut1), a tetrabromopyridine of melting point 105-106° is formed; this compound is 2,3,4,6-tetrabromopyridine. A very small quantity of pentabromopyridine is also formed.