AbstractThe reactivity of 2,4,6‐tribromopyridine‐towards dilute solutions of ammonia in water and butanol is described. The rate of the substitution reaction is higher in water than in the less polar butanol. In water the reagent attacks chiefly the bromine atom at the 4‐position, where the nucleus carries the highest positive electrical charge. In butanol the replacement of the bromine atoms at the 2‐ and 6‐positions is preponderant. Together with 2‐amino‐4,6‐dibromopyridine and 4‐amino‐2,6‐dibromopyridine, which compounds were known, 2,4‐diamino‐6‐bromopyridine was isolated as a reaction product.In agreement with the above‐mentioned results 2,4‐dichloronitrobenzene reacts more quickly with ammonia in water than in ethanol. While in the latter solvent during a reaction at 140° exclusively the ortho chlorine atom is replaced, in water, in addition to 2‐amino‐4‐chloronitrobenzene, some