Abstract
Acid dissociation constants of 5-acetyl-8-hydroxyquinoline have been determined by spectrophotometric and potentiometric methods at $25^{\circ}C$. $pK_1$, $pK_2$ values obtained by potentiometric method were 4.56, 8.20 respectively and $pK_1$ obtained by spectrophotometric method was 4.21. pK values were lower than those of 8-hydroxyquinoline. The lower basicity of 5-acetyl-8-hydroxyquinoline compared with 8-hydroxyquinoline was considered as the result of the electronic attraction of the acetyl group with aromatic ring.
5-Acetyl-8-hydroxyquinoline 의 酸解離定數를 $25^{\circ}C({\mu}$=0.1)에서 分光光度法과 pH滴定法에 依하여 測定하였다. 두 方法에 의하여 얻은 $pK_1$은 近似하게 一致하였으며 pK값은 8-hydroxyquinoline의 該當 pK값보다 작다. 그것은 acetyl group의 芳香族環에 대한 電子吸引性에 基因한 結果라고 생각한다.