Diaminotoluenes are synthetic aromatic aimines (total of 6 isomers). The isolated, purified isomers are colourless crystals, while the commercial isomeric mixtures are light yellow to tan (Meta-diaminotoluene), or light grey to purple (Ortho-diaminotoluene) solids. Diaminotoluenes are soluble in hot water, alcohol, ether, and hot benzene. When heated, they emit toxic fumes of nitrogen oxides.