摘要
本论文合成了四种哌嗪酮并氮杂环化合物和五种三亚甲基碳链连接的手性双咪唑啉配体,考察了这些手性咪唑啉化合物在不对称傅克烷基化反应中的应用,主要研究内容如下：
1.新型哌嗪酮并氮杂环化合物的合成及表征
以亚氨基二乙腈为起始原料,经三步反应,合成了四种新型的哌嗪酮并氮杂环化合物3a-3d (Scheme 1),化合物3a-3d均为新化合物,3a-3d通过了IR,1H NMR,13C NMR, MS和HRMS鉴定,其中化合物3c还经过单晶结构确证。
2.碳链连接的手性双咪唑啉配体的合成及表征
以戊二腈为起始原料,经两步反应合成了氮氢双咪唑啉化合物5,化合物5分别与对甲苯磺酰氯,酰氯或苄溴反应得到相应氮原子取代的双咪唑啉化合物6a-6d (Scheme 2)。其中化合物5和6a-6d均为新化合物,通过了IR,1H NMR, 13C NMR, MS和HRMS鉴定。
3.新型手性咪唑啉化合物在不对称傅克烷基化反应中的应用
初步研究了新合成的咪唑啉配体3c和6a-6d在不对称傅克烷基化反应中的应用,发现配体在吲哚与乙醛酸乙酯的反应中不对称诱导效果较好。在该反应中,考察了溶剂、反应温度、配体和金属盐的影响,发现双咪唑啉配体6a的催化效果较好(Scheme 3)。在较优条件下,使用10 mol% Zn(OTf)2/12 mol% 6a,在CH2Cl2中0℃反应24小时,各种取代的吲哚与乙醛酸乙酯反应可以达到良好的收率和最高60%的ee值。
In this thesis, four bicyclic nitrogen heterocycles containing piperazine compounds and five trimethylene carbon chain tethered bis(imidazoline) ligands were synthesized and characterized. These chiral imidazoline compounds were applied to asymmetric Fridel-Crafts alkylation reaction. The main results were shown as follows:
1. Synthesis and structural characterization of novel bicyclic nitrogen heterocycles containing piperazine compounds
Compounds 3a-3d were synthesized in three steps starting from iminodiacetonitrile 1 (Scheme 1). All of 3a-3d were new compounds and characterized by IR,1H NMR,13C NMR, MS and HRMS, the structure of 3c was also confirmed by X-ray Structure.
2. Synthesis and structural characterization of carbon chain tethered bis(imidazoline) ligands
Compound 5 was prepared from glutaronitrile 4 in two steps following the same general strategy, followed by condensation with p-methyl benzene sulfonic chloride,
引文
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