杯芳冠醚的合成及其催化合成对氟硝基苯

卤素交换氟化反应是合成含氟芳香化合物的重要方法之一,相转移催化剂对卤素交换氟化反应来说几乎是不可或缺的。本文以对叔丁基杯[4]芳烃和四甘醇二对甲苯磺酸酯为原料,在K₂CO₃存在下,合成了对叔丁基杯[4]-冠-5,将对叔丁基杯[4]-冠-5作为相转移催化剂应用于对氯硝基苯的氟化反应中,以检测其作为相转移催化剂在氟化反应中的催化活性,同时考察了反应时间、反应温度、不同相转移催化剂对卤素交换氟化反应的影响。结果表明对叔丁基杯[4]-冠-5对氟化反应具有相转移催化能力,研究发现以杯芳冠醚作相转移催化剂,使产品收率得到了明显提高。在对叔丁基杯[4]-冠-5的催化下,反应3h,反应的转化率和收率分别为96.53%、90.8%。

Synthesis of calixcrown ethers and its catalytic activity in synthesis of 4-fluoronitrobenzene

Halogen-exchange fluorination is the main method to synthesize fluorinated aromatics. Phase transfer catalysts (PTCs) are essential for the halogen-exchange fluorination. The p-tert-butylcalix[4]-arene- crown-5 was synthesized from p-tert-butylcalix[4]arene and tetraethylene glycol ditosylate in the presence of K₂CO₃, and it was used as the phase transfer catalyst in the fluoridation of chlorine nitrobenzene to investigate its performance in the fluorination. The influences of fluorination reaction conditions, such as the reaction time, temperature and different catalysts were investigated. The catalytic activities of p-tert-butylcalix[4]arene- crown-5 were verified. It was found that the yields of the reaction with p-tert-butylcalix[4]arene-crown-5 as PTC were improved. Catalyzed by p-tert-butylcalix[4]arene-crown-5 for 3 h, the reaction had a conversion of 96.53% and the yield of 4-fluoronitrobenzene was 90.8%.