8-羟基喹啉-5-甲醛和8-羟基喹啉-5-磺酸联产工艺研究

以8-羟基喹啉为原料,在酸性条件下与水合氯醛发生缩合反应得到5-（α-羟基-β-三氯）-8-羟基喹啉（Ⅰ）,联产8-羟基喹啉-5-磺酸（Ⅱ）.（Ⅰ）在碱性条件下水解生成8-羟基喹啉-5-甲醛（Ⅲ）,产物经熔点仪、元素分析仪、液-质联用仪、红外光谱仪及核磁共振氢谱等进行表征.探讨了反应温度、反应时间、原料比、溶剂及溶剂的重复性等因素对实验的影响.确定产物（Ⅰ）的最佳反应条件为：n（8-羟基喹啉）∶n（水合氯醛）∶n（硫酸）=1∶1.2∶4.6,反应温度为80℃,反应时间为12 h,产物收率为55％;产物（Ⅲ）的最佳反应条件为∶n（Ⅰ）∶n（KOH）=1∶5.1,回流反应7h,收率为21％.

Study on the Process of Joint Production of 8-Hydroxyquinoline-5-Carbaldehyde and 8-Hydroxyquinoline-5-Sulphonic Acid

5 - （ α - hydroxy - β - trichloroethyl） - 8 - hydroxyquinoline （ Ⅰ）, 8 - hydroxy quinoline - 5 - sulfohie acid （Ⅱ） was synthesized by reaction of 8 -hydroxyquinoline with chloral hydrate when sulfuric acid was used as solvent. 8 -hydroxylquinoline -5 -carbaldehyde was synthesized by reaction of （Ⅰ） with KOH in methanol. The structure of resultant was characterized with melting point detector, elemental analyzer, LC - MS, IR and 1 H NMR. The effects of temperature, reaction time, volumes of solvents, material ratio and reusability of solvents on the reaction were studied. The optimum conditions of （Ⅰ） were found as follows ： n （8 - hydroxyquinoline） ： n （ chloral hydrate） ： n （H2SO4） = 1： 1.2： 4.6, reaction temperature 80℃, reaction time 12 h, the yield of （Ⅰ） was 55 %. The optimumconditions of（Ⅲ） were found as follows ： n（Ⅰ） ： n（KOH） = 1： 5.1, reaction time 7h under reflow, the yield of （Ⅲ） was 21%.