Br?nsted酸性离子液体催化双酚芴的合成

Br?nsted Acidic Ionic Liquid Catalyzing the Synthesis of Biphenolfluorenone

摘要:

摘摘要：以1-甲基咪唑、1,3-丙磺酸内酯、硫酸、磷酸、四氟硼酸、对甲苯磺酸为原料，合成4种Brønsted酸性离子液体（ILs），并对其结构进行了表征，同时测定了离子液体的酸度H0。将离子液体应用于双酚芴的合成反应中，离子液体的酸度H0 ≤ 1.94时有催化作用，H0 ≤ 1.69的ILs催化剂有应用价值。明确了双酚芴合成反应的液相色谱定量分析方法。对反应产物进行分离，利用NMR确定了3种产物的结构。单变量优化法考察了反应参数对9-芴酮和苯酚缩合反应的影响，确定较优反应条件为：苯酚、9-芴酮和IL1的物质的量比为6∶1∶0.125，IL1和助催化剂巯基乙酸的物质的量比为5∶2，反应温度110℃，反应时间6 h。在上述条件下，考察了4种离子液体催化剂对双酚芴合成反应的催化效果，使用IL1、IL2、IL4催化反应时，9-芴酮转化率均为100%，双酚芴的选择性约为87%。此外，离子液体IL1连续使用5次催化效果无明显降低。

Abstract:

Abstract: Four Brønsted acidic ionic liquids (ILs) were synthesized using 1-methylimidazole, 1,3-propane sultone, sulfuric acid, phosphoric acid, tetrafluoroboric acid and p-toluene sulfonic acid as raw materials. Their structures were characterized and the acidity H0 was measured. These ionic liquids were applied to the synthesis of bisphenolfluorene. When the H0 was less than or equal to 1.94, the ionic liquid had cata-lytic effect, when that was less than or equal to 1.69, the ionic liquid had applicable value. A method for the determination of bisphenolfluorene by liquid chromatography was developed. The reaction products were separated and the structures of the three products were determined by NMR. The effect of reaction parameters on the condensation reaction of 9-fluorenone and phenol was investigated by univariate opti-mization. The optimal reaction conditions were obtained as follows: n(phenol): n(9-fluorenone): n(IL1)=6:1:0.125, n(IL1): n(thioglycolic acid)=5:2, reaction temperature 110℃ and reaction time 6 h. The catalytic effects of the four catalysts in the synthesis of bisphenolfluorene were investigated under the above conditions. For IL1, L IL2 and IL4 catalysts, the conversion of 9-fluorenone was 100%, and the selectivity of bisphenolfluorene was nearly 87%. In addition, the catalytic effect of ionic liquid IL1 was not significantly reduced after 5 consecutive uses.