铜催化醇有氧氧化制备腈和醛的反应研究

发布时间：2018-02-03 12:32

本文关键词： 醇氧化选择性氧化铜催化氧化腈化氨基酸氨水　出处：《浙江工业大学》2016年硕士论文　论文类型：学位论文

【摘要】：醇选择性氧化制备腈和醛是有机合成中一类非常重要的反应。本论文针对当前醇选择性氧化反应中存在的问题,发展了两类配体辅助调控铜催化醇选择性氧化制备腈和醛的新方法。设计了分别采用N-苯基甘氨酸和氨水作为有效配体,以氧气(或空气)为氧化剂,在油相(或水相)中高效、高选择性氧化芳香伯醇、烯丙基醇、杂环芳香醇为相应腈和醛的新体系。首先,氨基酸被选作一种N,O-二齿配体代替传统N,N-二齿配体,探究其在铜催化醇选择性氧化腈化反应中的作用。在以氨水(4.0 equiv.)为氮源的条件下,通过对各种天然氨基酸、功能化氨基酸、铜催化剂、溶剂、反应温度等影响因素的系统优化,得到最佳反应条件:底物醇(1.0 mmol)、CuI(5 mol%)、TEMPO(2,2,6,6-四甲基哌啶氧)(5 mol%)、N-苯基甘氨酸(5 mol%)、NaOH(10 mol%)、NH3(aq.25-28%w/w,300μL,4.0 mmol)、CH3OH(2.0 mL)。在最优条件下,一系列底物可以高选择性的氧化成目标产物,并显示出很好的官能团容忍性。此外,当反应规模放大后,底物转化率以及产物选择性并没有明显降低。结合研究结果以及相关报道,对可能的反应机理进行了探讨。其次,在水相中以氨水充当一种最简单的含氮配体,研究了铜催化一级醇选择性氧化的反应。通过对实验条件系统筛选,发现水相中一级醇选择性氧化制备腈或醛的过程可以通过控制氨水的用量实现。在最优条件下,当氨水的用量为8当量时,底物选择性转化为腈;当氨水的用量为7.9 mol%时,则选择性氧化为醛。另外,过量氨水的再利用实验结果表明,当氨水的用量从8当量降为3当量,经过5次循环再利用之后,反应的转化率和选择性没有明显的变化。
[Abstract]:Selective oxidation of alcohols to nitrile and aldehydes is a very important reaction in organic synthesis. Two kinds of ligands were developed to control the selective oxidation of copper catalyzed alcohols to produce nitrile and aldehydes. N- phenylglycine and ammonia were used as effective ligands respectively. Oxygen (or air) was used as oxidant. Highly selective oxidation of aromatic primary alcohols, allyl alcohols and heterocyclic aromatic aromatic alcohols in oil (or aqueous) phase is a new system of nitrile and aldehydes. N-didentate ligands were used to study the role of N-didentate ligands in the selective oxidation of nitrile alcohols catalyzed by copper. In the presence of ammonia water as nitrogen source, various natural amino acids were studied. The optimum reaction conditions of functional amino acid, copper catalyst, solvent, reaction temperature and so on were optimized. The optimum reaction conditions were obtained as follows: substrate 1. 0 mmol / L CuI + 5 mol / L). TEMPO2, 2, 2, 6, 6-tetramethylpiperidinoxomethoxy, 5 mols, 5 mols of N- phenylglycine and 10 mol of NaOHU). NH _ 3a _ Q _ (25-28) and w / w _ (300 渭 L) (4.0 mmol / L) Ch _ 3OH ~ (2 +) / L ~ (2. 0), under the optimum conditions. A series of substrates can be oxidized to target products with high selectivity and show good functional tolerance. In addition, when the scale of the reaction is enlarged. The substrate conversion and product selectivity were not significantly decreased. Combined with the results of the study and related reports, the possible reaction mechanism was discussed. Secondly, ammonia was used as the simplest nitrogen-containing ligand in aqueous phase. The selective oxidation of primary alcohols catalyzed by copper was studied. It is found that the process of selective oxidation of first-order alcohols to nitrile or aldehydes in aqueous phase can be achieved by controlling the amount of ammonia water. Under the optimal conditions, when the amount of ammonia water is 8 equivalent, the substrate can be selectively converted to nitrile. When the amount of ammonia water was 7.9 mol%, it was selectively oxidized to aldehydes. In addition, the reutilization experiment of excessive ammonia water showed that the amount of ammonia water decreased from 8 to 3 equivalent. After five reuses, the conversion and selectivity of the reaction did not change significantly.
【学位授予单位】：浙江工业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O621.251

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