In 1894, Henriques reported that bis(2-hydroxy-1-naphthyl) sulfide was converted to an isomeric dibasic substance by treatment with alkaline ferricyanide and a subsequent reduction of the intermediate obtained. Hinsberg carried out a similar sequence of reactions with bis(2-hydroxy 1 naphthyl) sulfone. The structures of the isomeric products of the two series were established by Smiles who recognized the occurrence of a novel intramolecular nucleophilic rearrangement.
This chapter surveys the reactions, which because of the extensive work of Smiles, have been called Smiles rearrangements. They may be characterized as intramolecular displacements at aromatic rings initiated by nucleophilic centers located two or three atoms distant from the functional group which is displaced.