A dinitronaphthalene reacts with alkali sulphides, and in particular with sodium hydrogen sulphide to form, mainly, a monoamine by reduction, and a sodium mercaptide by replacement of a nitro-with a sodium-thio-(SNa-) group, the ratio of these productsvarying according to the electropositivity of the carbon atom to which the reactive nitro-group is attached. 1: 2-or 1: 8-Dinitronaphthalene gives only mercaptan, whereas the 1: 3-, 1: 5-, 1: ...