| 摘要 |
PURPOSE:To obtain a new compound useful as an intermediate for synthesizing a photographic coupler. CONSTITUTION:A compound of formula I (R1 is alkyl, cycloalkyl, acryl or hetero atom; X is H, halogen, carboxyl, alkoxycarbonyl or aryloxycarbonyl) such as 5-amino-4-ethoxycarbonyl-3-(2-methoxyethoxy)-pyrazole. The compound of formula I is obtained by reacting a dicyanoketenedi-2-methoxyethyl acetal of formula II and subjecting to ring closure to give a pyrazole derivative, then treating the pyrazole derivative with concentrated hydrochloric acid in ethanol and optionally decarboxylating to give the compound of formula I. The compound is useful as a 1H-pyrazolo[3,2-c]-S-triazole-based photographic coupler, especially a synthetic intermediate for magenta coupler. |
