Abstract
2,6‐Dimethoxy‐benzoquinone (11) does not react with amines, such as ethylenimine, at room temperature nor at slightly elevated temperatures contrary to 2,5‐dimethoxy‐benzoquinone. In the 3,5‐dibromo‐2,6‐dimethoxy‐benzoquinone (VI), however, the same, previously unreactive methoxy groups are exchanged by amines. The two remaining bromine atoms can then be replaced by alkoxy or thioalkoxy groups (type IX). Reasons for this behaviour are discussed. The two halogen atoms in 2,5‐Diamino‐3,6‐dichloro‐benzoquinone are rather unreactive towards further treatment with amines. In 2,5‐bis‐acylamino‐3,6‐dichloro‐benzoquinones the halogen groups are highly reactive, so that they are exchanged by ethylenimine t o give compounds of type XVI.