| 摘要 |
PURPOSE:To produce a fluoran compound having slight color by dispersing a condensation reactional liquid in a mixture of an organic solvent and an alkaline aqueous solution, thereby performing the cyclization reaction taking advantage of the heat of neutralization and heat of dilution. CONSTITUTION:A 2-(2-hydroxybenzoyl)benzoic acid derivative of formula I (X is alkyl, alkoxy, halogen or substituted amino; (m) is 1-4) is subjected to condensation reaction with a phenol alkyl ether derivative of formula II (R is lower alkyl; Y is X; (m) is (n)) in concentrated sulfuric acid and the obtained condensation product is subjected to cyclization reaction to obtain a fluoran compound of formula III. In the above process, the condensation reactional liquid is added to a mixture of an alkaline aqueous solution and an organic solvent. The organic solvent is preferably toluene, xylene or monochlorobenzene and the alkaline aqueous solution is a solution of 1.0-1.3 equivalent of sodium hydroxide. |
