官能化二硫化物的相转移催化制备及还原研究
发布时间：2019-06-03 13:26
【摘要】：二硫化物在有机合成和生物体中具有重要的地位,生物体内二硫化物与巯基的可逆相互转化使得基于二硫化物的可生物降解材料在化学传感器、前体药物、水凝胶和纳米材料等领域广泛应用。本论文研究了通过相转移催化合成官能化二硫化物中各种反应条件的影响和相转移催化机理,利用相转移催化合成了双(羟基十一烷基)二硫化物和聚烷基二硫化物,并使用不同的还原剂对双(羟基十一烷基)二硫化物进行还原,探讨了DTT在不同溶剂体系中还原二硫化物的能力,提出了DTT还原二硫化物的反应机理,主要研究结论包括:1、通过对相转移催化合成烷基二硫化物过程中反应温度、反应时间、物料比等因素的研究,第I步反应中硫磺与硫化钠的配比决定了生成二硫根的反应平衡,决定了反应完毕后单硫根、二硫根和三硫根离子的浓度。2、相转移催化合成烷基二硫化物的第II步反应中,三种硫根离子与双十二烷基二甲基铵离子的结合能力顺序为:单硫根二硫根三硫根;相转移催化制备二硫化物过程中,硫根离子的浓度及其与相转移活性离子的结合能力决定了哪种离子能够被转移并生成相应的产物。3、利用相转移催化反应,通过控制优化的反应条件,可以制得纯度很高的双(羟基十一烷基)二硫化物;此外,调节Na2S2和1,10-二溴癸烷的摩尔比,在适当的反应条件下可以制备聚癸烷基二硫化物,这种聚合物为无色透明的聚合物。4、在双(羟基十一烷基)二硫化物的还原反应中,使用硼氢化钠作为还原剂可实现的还原比例为70%;使用Zn-乙酸体系可以实现还原率为80%,但易造成羟基的酯化反应;Zn-HCl体系的还原率为53%;三丁基膦基本上未发现还原活性。5、DTT还原双(羟基十一烷基)二硫化物与溶剂性质密切相关。在THF为主溶剂的体系中,随着质子性溶剂(水、甲醇)含量的增加,还原率越来越高,最高达到95.6%;在二氯甲烷为主溶剂体系中,当完全无水时,还原反应不能发生,而水含量仅为0.05%时,还原率可达到73.6%,然后随着水含量的增加而还原率降低。6、从反应机理来看,碱性条件下,二硫苏糖醇的两个巯基电离为硫离子,这种硫离子作为亲核试剂对二硫键中的硫原子进攻,在水、甲醇等质子性溶剂的促进作用下,使得二硫键断裂,形成硫离子;而二硫苏糖醇的两个硫原子闭环被氧化。
[Abstract]:Disulfide plays an important role in organic synthesis and organisms. The reversible transformation of disulfide and sulfhydryl groups in organisms makes disulfide-based biodegradable materials in chemical sensors, precursor drugs, Hydrogel and nanomaterials are widely used in the field of hydrogel and nanomaterials. In this paper, the effects of reaction conditions and the mechanism of phase transfer catalysis on the synthesis of functionalized disulfide by phase transfer catalysis were studied, and bis (hydroxyundecyl) disulfide and polyalkyl disulfide were synthesized by phase transfer catalysis. The ability of DTT to reduce disulfide in different solvent systems was discussed by using different reductants. The reaction mechanism of DTT reduction of disulfide was put forward. The main conclusions are as follows: 1. By studying the reaction temperature, reaction time and material ratio in the synthesis of alkyl disulfide by phase transfer catalysis, the reaction equilibrium of the formation of disulfide is determined by the ratio of sulfur to sodium sulfide in the first step. The concentration of monosulfide, disulfide and trisulfide ions after the reaction was determined. 2. In the second step of the synthesis of alkyl disulfide by phase transfer catalysis, The order of binding ability of three sulfur ions to dialkyl dimethyl ammonium ion is as follows: monosulfide disulfide trisulfide; In the process of phase transfer catalysis to prepare disulfide, the concentration of sulfur ion and its binding ability to phase transfer active ion determine which ion can be transferred and form the corresponding product. 3, using phase transfer catalytic reaction, By controlling the optimized reaction conditions, the bis (hydroxyundecyl) disulfide with high purity can be prepared. In addition, polydecyl disulfide can be prepared by adjusting the molar ratio of Na2S2 to 1, 10-dibromodecane under appropriate reaction conditions, which is a colorless and transparent polymer. 4, In the reduction reaction of bis (hydroxyundecyl) disulfide, the reduction ratio can be realized by using sodium borohydrate as reductant. The reduction rate of Zn- acetic acid system is 80%, but it is easy to cause the esterification of hydroxyl group, and the reduction rate of Zn-HCl system is 53%. The reduction activity of tributylphosphine was basically not found. 5, the reduction of bis (hydroxyundecyl) disulfide by DTT was closely related to the properties of solvent. In the system of THF as the main solvent, with the increase of the content of protonic solvent (water, methanol), the reduction rate is higher and higher, the highest is 95.6%. In the main solvent system of dichloromethane, when there is no water, the reduction reaction can not occur, and when the water content is only 0.05%, the reduction rate can reach 73.6%, and then the reduction rate decreases with the increase of water content. From the point of view of reaction mechanism, two sulfhydryl groups of dithiothreitol were ionized into sulfur ions under alkaline conditions, which were used as nucleophilic reagents to attack sulfur atoms in disulfide bonds, promoted by protonic solvents such as water and methanol. The disulfide bond is broken and sulfur ion is formed. The two sulfur atoms of dithiothreitol are oxidized in closed loop.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36
本文编号：2491962
[Abstract]:Disulfide plays an important role in organic synthesis and organisms. The reversible transformation of disulfide and sulfhydryl groups in organisms makes disulfide-based biodegradable materials in chemical sensors, precursor drugs, Hydrogel and nanomaterials are widely used in the field of hydrogel and nanomaterials. In this paper, the effects of reaction conditions and the mechanism of phase transfer catalysis on the synthesis of functionalized disulfide by phase transfer catalysis were studied, and bis (hydroxyundecyl) disulfide and polyalkyl disulfide were synthesized by phase transfer catalysis. The ability of DTT to reduce disulfide in different solvent systems was discussed by using different reductants. The reaction mechanism of DTT reduction of disulfide was put forward. The main conclusions are as follows: 1. By studying the reaction temperature, reaction time and material ratio in the synthesis of alkyl disulfide by phase transfer catalysis, the reaction equilibrium of the formation of disulfide is determined by the ratio of sulfur to sodium sulfide in the first step. The concentration of monosulfide, disulfide and trisulfide ions after the reaction was determined. 2. In the second step of the synthesis of alkyl disulfide by phase transfer catalysis, The order of binding ability of three sulfur ions to dialkyl dimethyl ammonium ion is as follows: monosulfide disulfide trisulfide; In the process of phase transfer catalysis to prepare disulfide, the concentration of sulfur ion and its binding ability to phase transfer active ion determine which ion can be transferred and form the corresponding product. 3, using phase transfer catalytic reaction, By controlling the optimized reaction conditions, the bis (hydroxyundecyl) disulfide with high purity can be prepared. In addition, polydecyl disulfide can be prepared by adjusting the molar ratio of Na2S2 to 1, 10-dibromodecane under appropriate reaction conditions, which is a colorless and transparent polymer. 4, In the reduction reaction of bis (hydroxyundecyl) disulfide, the reduction ratio can be realized by using sodium borohydrate as reductant. The reduction rate of Zn- acetic acid system is 80%, but it is easy to cause the esterification of hydroxyl group, and the reduction rate of Zn-HCl system is 53%. The reduction activity of tributylphosphine was basically not found. 5, the reduction of bis (hydroxyundecyl) disulfide by DTT was closely related to the properties of solvent. In the system of THF as the main solvent, with the increase of the content of protonic solvent (water, methanol), the reduction rate is higher and higher, the highest is 95.6%. In the main solvent system of dichloromethane, when there is no water, the reduction reaction can not occur, and when the water content is only 0.05%, the reduction rate can reach 73.6%, and then the reduction rate decreases with the increase of water content. From the point of view of reaction mechanism, two sulfhydryl groups of dithiothreitol were ionized into sulfur ions under alkaline conditions, which were used as nucleophilic reagents to attack sulfur atoms in disulfide bonds, promoted by protonic solvents such as water and methanol. The disulfide bond is broken and sulfur ion is formed. The two sulfur atoms of dithiothreitol are oxidized in closed loop.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36
【参考文献】
相关期刊论文 前2条
1 李春鸽;赵爽;李俊杰;尹玉姬;;含巯基/二硫键聚合物生物材料[J];化学进展;2013年01期
2 李新芳,王学业,文小红,龙清平,刘万强,谭援强,李建军;有机二硫化物极压添加剂结构与润滑性能的理论研究[J];摩擦学学报;2005年01期
，本文编号：2491962
本文链接：https://www.wllwen.com/kejilunwen/huaxue/2491962.html
教材专著
