反应详情

In a manner similar to that described in Example 1 above, 5.2 g of 2-(4-dimethylaminophenyl)carbonyl-5-dimethylaminobenzoic acid, 1.2 ml of thionyl chloride and 5.0 ml of methyl alcohol were interacted in 30.0 ml of ethylene dichloride in the presence of 1.3 ml of pyridine at ambient temperature overnight to obtain 4.5 g of 3-methoxy-3-(4-dimethylaminophenyl)-6-dimethylaminophthalide (Formula II: R0 =R=R2 =R5 =H; R1 =N(CH3)2 ; R4 =R4' =Y=CH3 ; X=O), a pale green-colored solid which melted over the range of 141° to 149° C. An infrared maximum appeared at 1770 cm-1 (C=O;s). The nuclear magnetic resonance spectrum was consistent with the assigned structure. Analysis by mass spectrum showed m/e peaks at 326 (M+) and 295 (M+ -OCH3). A toluene solution of the product spotted on an acidic clay-coated paper developed a green-colored image.