| 摘要 |
<p>5-Trifluoromethyl benzimidazole, (or its derivs.), of formula (where R = H, F, Br or I, R1 = alkyl or aryl, R2 = alkyl, aryl or one of: (where R3, R4, R5 and R6 = lower alkyl) are prepared by reacting 3-nitrobenzenetrifluoride with an arylor alkylamine to give an aniline deriv, which is reacted in the presence of a catalyst (Pd) and solvent to give a diamine. The diamine is reacted with an acid anhydride (pref. (CH3CO)2O) to give benzimidazole, which is nitrated, reduced and further halogenated as required. Compsns. are useful sensiters in colour photography.</p> |
