Synthesis of Novel Colorless DAR Couplers

The improvement of the color photographic materials having higher photosensitivity and smaller granularily,owes much to the developent accelerator releasing couplers.With 〔5-mercapto-(1,3,4) thiadiazol-2-yl-thio〕-acetic acid adopted as the adsorption group and formic acid 2-(4-amino-pheny1)-hydrazide,acetic acid 2-(4-amino-pheny1)-hydrazide and trifluoro-acetic acid 2-(4-amino-pheny1)-hydrazide as the strengthen groups respectively,three new colorless DAR(YKA,YKB,YKC) couplers were synthesized from N,N'-bis-(2-chloro-5-n-dodecyloxy-carbony1) phenylmalonamide.The intermediates and the target compounds were characterized and confirmed by means of IR,MS,1HNMS.