【作者】 马庆国；

【导师】 彭新华；

【作者基本信息】 南京理工大学 ， 化学工程与技术， 2015， 博士

【摘要】 酯在香料、农药及医药等领域具有重要的应用价值,以过氧化氢溶液为氧化剂,通过Baeyer-Villiger氧化反应合成内酯或酯的中间体受到越来越广泛的关注。本论文以过氧化氢溶液为氧化剂,研究了不同催化剂在催化环酮的Baeyer-Villiger氧化反应中的催化活性及催化作用机理。分别介绍了以过氧酸、分子氧或过氧化氢溶液为氧化剂的Baeyer-Villiger反应的研究进展,阐述了以过氧化氢溶液为氧化剂的Baeyer-Villiger反应所面临的机遇与挑战,概述了选题意义及研究内容。以过氧化氢溶液为氧化剂,比较了不同过渡金属氧化物在催化2-庚基环戊酮的Baeyer-Villiger反应中的催化活性。M003和W03的催化活性高于TiO2、Fe2O3、Co3O4. ZnO和Zr02的催化活性。Mo03和W03催化以过氧化氢溶液为氧化剂的2-庚基环戊酮的Baeyer-Villiger反应的催化机理不同于TiO2、Fe2O3、Co3O、ZnO和Zr02。通过紫外-可见吸收光谱分别研究了Mo03和过氧化氢溶液、Mo03和蒸馏水、Mo03和2-庚基环戊酮的相互作用。研究了反应温度、催化剂用量、过氧化氢溶液用量、过氧化氢溶液浓度及溶剂对MoO3或W03催化2-庚基环戊酮的Baeyer-Villiger氧化反应的影响。环酮的反应活性相差较大,当与酮羰基碳相邻的碳原子是叔碳的环酮(金刚烷酮和2-甲基环己酮)时,发生Baeyer-Villiger氧化反应的反应活性及生成相应内酯的选择性都较高,产率都在91%以上。提出了以过氧化氢溶液为氧化剂,以Mo03或W03为催化剂催化环酮的Baeyer-Villiger氧化反应机理。分别以SnCl2和SnCl4为负载剂,通过沉淀法制备了锡改性的硅藻土。通过红外光谱和X-射线粉末衍射对制备的催化剂进行了表征。以质量分数为30%的过氧化氢溶液为氧化剂,比较了SnCl2、SnCl4和锡改性的硅藻土在催化2-庚基环戊酮的Baeyer-Villiger氧化反应中的催化活性。负载后催化剂的催化活性弱于SnCl2和SnCl4。锡改性的硅藻土催化以过氧化氢溶液为氧化剂的2-庚基环戊酮的Baeyer-Villiger反应的催化作用机理不同于SnCl2和SnCl4。研究了反应温度、催化剂用量、过氧化氢溶液用量、过氧化氢溶液浓度及溶剂对锡改性的硅藻土催化2-庚基环戊酮的Baeyer-Villiger氧化反应的影响。当与酮羰基碳相邻的碳原子是叔碳的环酮(金刚烷酮和2-甲基环己酮)时,发生Baeyer-Villiger氧化反应的反应活性及生成相应内酯的选择性都较高,产率都在76%以上。以质量分数为30%的过氧化氢溶液为氧化剂,比较了不同Brφpnsted酸在催化2-庚基环戊酮的Baeyer-Villiger氧化反应中的催化活性。在同等条件下,磷钨酸的催化活性最高,2-庚基环戊酮的转化率达到了97.1%。研究了反应温度、催化剂用量、过氧化氢溶液用量及溶剂对磷钨酸催化2-庚基环戊酮的Baeyer-Villiger氧化反应的影响。当与酮羰基碳相邻的碳原子是叔碳的环酮(金刚烷酮和2-甲基环己酮)时,发生Baeyer-Villiger氧化反应的反应活性及生成相应内酯的选择性都较高,产率都在70%以上。以磷钨酸为负载剂,分别以高岭土、皂土和硅藻土为载体,制备了不同载体负载的磷钨酸催化剂。分别对催化剂的结构进行了红外光谱和X-射线粉末衍射分析,研究发现,负载后的催化剂保持了磷钨酸的Keggin结构。以质量分数为30%的过氧化氢溶液为氧化剂,比较了不同载体负载的磷钨酸在催化2-庚基环戊酮的Baeyer-Villiger氧化反应中的催化活性。在同等条件下,以硅藻土负载的磷钨酸的催化活性最高,2.庚基环戊酮的转化率为98.3%。在负载条件相同,负载量一致的条件下,催化剂的催化活性随着载体(高岭土、皂土和硅藻土)的硅铝比的下降而升高。研究了反应温度、催化剂用量、过氧化氢溶液用量及溶剂对硅藻土负载的磷钨酸催化2.庚基环戊酮的Baeyer-Villiger氧化反应的影响。当与酮羰基碳相邻的碳原子是叔碳的环酮(金刚烷酮和2-甲基环己酮)时,环酮发生Baeyer-Villiger氧化反应的反应活性及生成相应内酯的选择性都较高,产率都在72%以上。通过控制碳酸钾的物质的量,以滴定法制备了氢元素含量不同的磷钨酸盐(KHPW、K2.5H0.5PW和ICPW)。对催化活性高、稳定性好并可重复使用的催化剂(K2.5H0.5PW)的结构进行了红外光谱分析、X.射线粉末衍射分析和热重分析。制得的磷钨酸盐催化剂(KHPW、K2.sH0.5PW和KPW)的结构与磷钨酸对比发现,磷钨酸原有的Keggin结构没有发生根本的改变。以质量分数为30%的过氧化氢溶液为氧化剂,比较了不同磷钨酸盐在催化2-庚基环戊酮的Baeyer-Villiger氧化反应中的催化活性。研究发现K2.5H0.5PW兼有催化活性高、稳定性好和可重复使用的优点。研究了反应温度、催化剂用量、过氧化氢溶液用量及溶剂对K2.5H0.5PW催化2-庚基环戊酮的Baeyer-Villiger氧化反应的影响。当与酮羰基碳相邻的碳原子是叔碳的环酮(金刚烷酮和2-甲基环己酮)时,发生Baeyer-Villiger氧化反应的反应活性及生成相应内酯的选择性都较高,产率都在81%以上。以过氧化氢溶液为氧化剂,对在不同催化条件下的Baeyer-Villiger氧化反应进行了总结和展望。更多还原

【Abstract】 Baeyer-Villiger oxidation using aqueous hydrogen peroxide as oxidant in organic unit process is considerable interest to the preparation of lactone and ester intermediates in perfumes, agrochemicals, pharmaceuticals etc. The catalytic activity of different catalysts in the Baeyer-Villiger oxidation of cyclic ketones with aqueous hydrogen peroxide as oxidant was studied. The reaction mechanism of Baeyer-Villiger oxidation of cyclic ketones under different catalytic systems was studied.Research progress of Baeyer-Villiger reaction using peracid, dioxygen or aqueous hydrogen peroxide as oxidant was reviewed. The opportunities and challenges remained in the Baeyer-Villiger reaction were elaborated. Significance of the research topic and research contents were summarized.The catalytic activity of transition metal oxides were compared in the Baeyer-Villiger oxidation of 2-heptylcyclopentanone using aqueous hydrogen peroxide as oxidant. The catalytic activity of MoO3 and WO3 was higher than TiO2, Fe2O3, CO3O4, ZnO and ZrO2. The differences in the catalytic activity of the studied transition metal oxides were obviously related to the differences in their catalytic mechanisms. UV/visible absorption spectra were used for detecting the interaction of MoO3/H2O2, MoO3/H2O and MoO3/2-heptylcyclopentanone. The influences of reaction temperature, molar ratio of hydrogen peroxide to 2-heptylcyclopentanone, concentration of aqueous hydrogen peroxide, amount of catalyst and solvents to the Baeyer-Villiger oxidation were studied. The reactivity of cyclic ketones is notably different, the cyclic ketones (2-adamantanone, 2-methyl cyclohexanone) with tertiary carbon bonded to the carbonyl carbon have higher selectivity to the corresponding lactones than those with secondary carbon, the yield of corresponding lactones were higher than 91%. Additionally, the reaction mechanism of Baeyer-Villiger oxidation of cyclic ketones on MoO3 and WO3 was proposed.A metal tin modified diatomaceous earth was prepared, its structure was characterized by IR spectra and X-ray diffraction spectra. The catalytic activity of SnCl2, SnCl4 and tin modified diatomaceous earth were compared in the Baeyer-Villiger oxidation of 2-heptylcyclopentanone using aqueous hydrogen peroxide as oxidant. The catalytic activity of tin modified diatomaceous earth was lower than SnCl2 and SnCl4. the catalytic mechanism in the Baeyer-Villiger oxidation catalyzed by tin modified diatomaceous earth was different from the catalytic mechanism in the Baeyer-Villiger oxidation catalyzed by SnCl2 and SnCl4. The influences of reaction temperature, molar ratio of hydrogen peroxide to 2-heptylcyclopentanone, concentration of aqueous hydrogen peroxide, amount of catalyst and solvents to the Baeyer-Villiger oxidation were studied. The cyclic ketones (2-adamantanone,2-methyl cyclohexanone) with tertiary carbon bonded to the carbonyl carbon have higher selectivity to the corresponding lactones than those with secondary carbon, the yield of corresponding lactones were higher than 76%.The catalytic activity of different Brcpnsted acid were compared in the Baeyer-Villiger oxidation of 2-heptylcyclopentanone to δ-dodecalactone using aqueous hydrogen peroxide as a clean oxidant.12-Tungstophosphoric acid seems to be a rather efficient and highly selective catalyst for the Baeyer-Villiger reaction of 2-heptylcyclopentanone to δ-dodecalactone. The influences of reaction temperature, molar ratio of hydrogen peroxide to 2-heptylcyclopentanone, amount of catalyst and solvents to the Baeyer-Villiger oxidation were studied. The cyclic ketones with tertiary carbon bonded to the carbonyl carbon have higher selectivity to the corresponding lactones than those with secondary carbon, the yield of corresponding lactones were higher than 70%.12-tungstophosphoric acid was immobilized on different clay via impregnation in aqueous solution. For characterization of the catalysts, FT-IR and XRD were employed, which showed that there was no decomposition of the HPW Keggin structure during material preparation. The prepared catalysts were tested in the Baeyer-Villiger oxidation of 2-heptylcyclopentanone using aqueous hydrogen peroxide as oxidant. The 12-tungstophosphoric acid supported diatomaceous earth was found to be the best catalyst, based on high conversion of 2-heptylcyclopentanone (98.3%). It was observed that the catalytic activity increases with the ratio of Al2O3:SiO2 decreases. The influences of reaction temperature, molar ratio of hydrogen peroxide to 2-heptylcyclopentanone, amount of catalyst and solvents to the Baeyer-Villiger oxidation were studied. The cyclic ketones (2-adamantanone,2-methyl cyclohexanone) with tertiary carbon bonded to the carbonyl carbon have higher selectivity to the corresponding lactones than those with secondary carbon, the yield of corresponding lactones were higher than 72%.The salts of 12-tungstophosphoric acid catalysts are prepared with varying potassium content. For characterization of the catalysts, FT-IR and XRD were employed, which showed that there was no decomposition of the HPW Keggin structure during material preparation. The prepared catalysts were tested in the Baeyer-Villiger oxidation of 2-heptylcyclopentanone using aqueous hydrogen peroxide as oxidant. K2.5H0.5PW is the preferred catalyst in the reaction, based on its reusability, environmental benefits and high conversion of 2-heptylcyclopentanone. The influences of reaction temperature, molar ratio of hydrogen peroxide to 2-heptylcyclopentanone, amount of catalyst and solvents to the Baeyer-Villiger oxidation were studied. The cyclic ketones (2-adamantanone,2-methyl cyclohexanone) with tertiary carbon bonded to the carbonyl carbon have higher selectivity to the corresponding lactones than those with secondary carbon, the yield of corresponding lactones were higher than 81%. Additionally, the reaction mechanism of Baeyer-Villiger oxidation of cyclic ketones on K2.5H0.5PW was proposed.A briefly summary and prospect of Baeyer-Villiger oxidation using aqueous hydrogen peroxide as oxidant were given.更多还原