DYE RELEASERS FOR INSTANT COLOR-PHOTOGRAPHY - MOLECULAR DESIGN AND SYNTHETIC DESIGN

Molecular and synthetic design of o-sulfonamidophenol dye-releasers for instant color photography is described. These dye-releasers are oxidized to the corresponding o-quinone monosulfonamides, which are in turn hydrolyzed to release diffusible dyes. The efficiency of the dye-releasing proces is influenced by substituents on the phenyl group of the o-sulfonamidophenyl moiety. Side reactions of the intermediate o-quione monosulfonamides are reduced by steric hindrance of t-alkyl substituents. The effects of substitutents on the heat-fastness of released dyes are discussed. Several unit reactions are developed: e.g. benzoxazole synthesis, convenient methods of preparing sulfonyl chlorides, a procedure of nuclepophilic substitution of aromatic ring, and a new reducing agent of quinones.