MCM-41 负载席夫碱催化α,β-不饱和酮的环氧化反应研究

介孔分子筛MCM-41 依次与3-氯丙基三乙氧基硅烷、环己二胺和三唑醛反应, 得到席夫碱修饰的新型介孔分子筛MCM-41 催化剂. 通过傅里叶变换红外光谱(FTIR)和X 射线多晶衍射(XRD)等方法对所得催化剂进行表征. 以过氧化氢为氧源, 介孔分子筛MCM-41 负载的席夫碱为催化剂, 研究了α,β-不饱和酮的环氧化反应, 考察了金属盐、溶剂、催化剂用量、反应时间等因素对环氧化反应的影响. 结果表明, 在室温下乙腈溶剂中, α,β-不饱和酮的环氧化反应在短时间内均以很高的产率(高达99%)得到了相应的产物. 同时, 对催化剂的重复利用进行了研究, 发现重复使用四次, 仍能以较高产率得到环氧化产物.     

Study on the Epoxidation of a, β-Unsaturated Ketones Catalyzed by MCM-41 Supported Schiff Base

介孔分子筛MCM-41依次与3-氯丙基三乙氧基硅烷、环己二胺和三唑醛反应,得到席夫碱修饰的新型介孔分子筛MCM-41催化剂.通过傅里叶变换红外光谱（FTIR）和X射线多晶衍射（XRD）等方法对所得催化剂进行表征.以过氧化氢为氧源,介孔分子筛MCM-41负载的席夫碱为催化剂,研究了α,β-不饱和酮的环氧化反应,考察了金属盐、溶剂、催化剂用量、反应时间等因素对环氧化反应的影响.结果表明,在室温下乙腈溶剂中,α,β-不饱和酮的环氧化反应在短时间内均以很高的产率（高达99%）得到了相应的产物.同时,对催化剂的重复利用进行了研究,发现重复使用四次,仍能以较高产率得到环氧化产物.     

功能化MCM-41在有机合成中的应用

介孔分子筛MCM-41具有较高的比表面和规整的结构以及表面带有羟基,因此可对MCM-41进行官能团化,从而实现均相催化剂在MCM-41中的组装,达到均相催化剂多相化的目的。本文介绍了最近几年以MCM-41为主体,组装均相配合物得到固相化催化剂在氧化、还原、烷基化、氢甲酰化、Heck、环丙烷化等反应中的应用。     

介孔分子筛MCM-41固载席夫碱与Cu(ClO_4)_2·6H_2O催化合成螺[吲哚-噻唑啉酮]衍生物

利用介孔分子筛纳米反应器MCM-41@席夫碱-Cu(ClO_4)_2·6H_2O作为非均相催化剂,简单高效地催化靛红-3-亚胺和巯基乙酸进行迈克尔加成-缩合反应,合成了一系列的螺[吲哚-噻唑啉酮]衍生物,收率最高可达99%.另外,发现具有相同官能团的非均相催化剂比均相催化剂表现出更好的催化效果,并进一步探索了介孔分子筛纳米反应器MCM-41孔道结构对该反应的影响.此类催化剂可回收再利用,催化循环6次后仍能得到93%的产率.     

BrΦnsted酸性离子液体[HSO3-bpy][HSO4]催化合成β-吲哚酮

以BrΦnsted酸性离子液体[HSO3-bpy][HSO4]为催化剂, 将吲哚或取代吲哚与α,β-不饱和酮在乙腈中于80 ℃下反应3 h, 以92%～98%的产率制备了一系列的β-吲哚酮. 该方法简便易行且产率高. 催化剂离子液体对环境友好, 并可循环使用.     

乙二胺基和2，4-戊二酮官能化介孔分子筛固载钼（Ⅵ）：新型的环己烯环氧化催化剂

通过对介孔分子筛HMS和MCM-41表面修饰，将乙二胺基和2，4-戊二酮引入到介 孔分子筛孔道内，制备出乙二胺基和戊二酮官能化介孔分子筛。首次将烯烃环氧化 均相催化剂MoO_2(acac)_2固载到乙二胺基和戊二酮官能化介孔分子筛孔道内，制 备出新型的、易回收、可重复使用的烯烃环氧化多相催化剂。环已烯催化环氧化表 明，该催化剂的催化活性与均相催化剂MoO_2(acac)_2相当，选择性大于80%。     

有机磷化合物的研究(Ⅴ)——二硫代磷酸酯与醛、酮的反应

本文报导了O,O-二烷基二硫代磷酸酯作试剂,在正丁基锂作用下与醛、酮化合物反应制备α,β-不饱和羧酸酯、α,β-不饱和酰胺及α,β-不饱和腈的合成方法.该试剂在相同条件下与醛、酮反应无显著差别.均得到了较满意的结果.     

烯基取代的甲酸态四氢叶酸辅酶模型的合成及其碳单元转移反应

以邻苯二胺和乙酸为原料,经3步反应合成了8种烃基乙烯基取代的苯并咪唑盐,其结构用元素分析,¹HNMR,IR,MS和UV-Vis进行了表征,并以其作为取代的甲酸态四氢叶酸辅酶模型,同亲核试剂(格氏试剂)反应得到烃基乙烯基取代的一碳单元完全转移的产物α,β-不饱和酮,为α,β-不饱和酮的合成提供了一种简便的仿生合成新方法.     

介孔分子筛MCM-41固载多氮杂环席夫碱与偏钒酸钠共催化氧化苯一步制备苯酚

2-苯基-1,2,3-三唑醛和喹喔啉醛通过亚胺键固载到介孔分子筛MCM-41上,得到6种MCM-41固载多氮杂环席夫碱(L1~L6),用FT-IR、XRD和SEM等技术手段对所制得的固载席夫碱进行表征。 研究了以MCM-41固载多氮杂环席夫碱和金属盐偏钒酸钠为共同催化剂,过氧化氢为氧源,直接催化氧化苯合成苯酚,用气相色谱快速检测苯酚产率。 系统地考察了配体、金属盐、温度、溶剂、催化剂用量、反应时间、氧化剂等因素对反应的影响,产率最佳可达23.9%,选择性大于90%。 对催化剂扩大5倍量进行试验,得到23%的产率和93%的选择性,并且催化剂重复使用3次仍能达到19%的产率和90%以上的选择性。     

介孔分子筛MCM-41负载钯催化剂催化合成α-芳基酮化合物的研究

以芳基酮和溴代芳烃为原料,介孔分子筛MCM-41负载钳形钯配合物为催化剂,研究了一种制备α-芳基酮化合物的方法.结果表明:在催化剂用量1.0％,反应时间2 h,反应温度81℃的条件下,负载型钯催化剂可以高效催化生成α-芳基酮化合物,产率可达94％.该反应官能团兼容性好,底物范围广,催化剂重复使用5次,活性未出现明显降低...     

手性联萘酚配合物催化的缺电子烯烃不对称环氧化反应

缺电子烯烃的不对称环氧化反应是有机合成领域最具有挑战性的课题之一。手性联萘酚配体所修饰的催化剂是一种很优异的C2轴对称手性诱导源,可以催化各种α,β－不饱和羰基化合物如α,β－不饱和酮、α,β－不饱和羧酸脂等的不对称环氧化反应,具有良好的催化活性和对映选择性。本文对由手性联萘酚类配体所修饰的小分子催化剂、聚合物负载的催化剂和自负载催化剂在不饱和羰基化合物的催化不对称环氧化反应中的应用进行了综述,探讨了催化剂结构、配位金属原子、添加物、氧化剂、溶剂和反应温度等因素对手性联萘酚催化剂催化效能和对映选择性的影响。     

Direct one-pot synthesis of zolimidine pharmaceutical drug and imidazo[1,2-a]pyridine derivatives via I2/CuO-promoted tandem strategy

An effi cient one-pot synthetic protocol was developed for the synthesis of imidazo[1,2-a] pyridines from easily available starting materials. All the desired products were obtained in moderate to good yields. Moreover, this protocol can also be further applied towards the synthesis of the marketed antiulcer drug zolimidine with 95% yield     

Stereoselective Synthesis of Sulfonyl-substituted trans-2,3-Dihydrofuran Derivatives via Reaction of Arsonium Ylides with α,β-Unsaturated Ketones

Trans-2,3-dihydrofuran derivatives 3 or 4 substituted with a sulfonyl group were prepared with high chemoselectivity and good yields by [1＋4]-addition reaction of α,β-unsaturated ketones 1 with arsonium bromide 2 in CH2Cl2 in the presence of potassium carbonate at room temperature.The structures of the products were characterized by IR,MS,^1H NMR,elemental analysis and single crystal X-ray diffraction analysis.A mechanism for the formation of products was also proposed.     

纳米贵金属插入的粘土用于催化选择性加氢反应

 The use of clay minerals in the synthesis of nanosized noble metal particles to give increased catalytic activity was investigated. Nanosized platinum and ruthenium catalysts intercalated in clay (montmorillonite/hectorite) were synthesised and their catalytic activity was evaluated for the selective hydrogenation of three different α,β-unsaturated aldehydes, namely, crotonaldehyde, cinnamaldehyde, and citral, in a gas phase microreactor. The metal nano-sol was prepared by the chemical reduction of its precursor by the micellar technique in the presence of cetyl trimethyl ammonium bromide (CTAB), and the micelle stabilized metal particles were intercalated in the clay mineral by ion exchange. TEM micrographs of the catalyst particles showed that the metal particles were in the nanometre range. The average diameters of the particles were 1–25 nm. The effects of temperature, metal loading, and hydrogen flow rate on the catalytic activity and selectivity for α,β- unsaturated alcohol were studied. The results were correlated with the structural properties of the catalysts. The products formed in each reaction over the different catalysts showed that the catalysts were very active for hydrogenation, and the selectivity for the desired product, namely, α,β-unsaturated alcohol, was good. The metal catalysts intercalated in montmorillonite showed better selectivity than that in hectorite because of its higher acidity. Increased selectivity for α,β-unsaturated alcohol was observed with increased flow rate of hydrogen.     

镍(II)配合物官能化的MCM-41催化分子氧环氧化苯乙烯

制备了镍(II)席夫碱配合物官能化的MCM-41多相催化剂MCM-41-Ni.利用X射线粉末衍射、氮气物理吸附脱附、红外光谱、热重、电感耦合等离子体原子发射光谱、元素分析和透射电镜等方法对催化剂进行了表征.以氧气为氧化剂,MCM-41-Ni在催化环氧化苯乙烯的反应中表现出较高的催化活性;苯乙烯的转化率为95.2%,环氧苯乙烷的选择性为66.7%.系统地研究了反应温度、催化剂用量、溶剂以及反应时间对反应性能的影响.催化剂经过4次循环仍然表现出较好的稳定性和催化活性.     

3-（CH2）nCO2C2H5-1,5-苯并硫氮杂的合成、晶体结构及抑真菌活性

为了寻找具有更高抗真菌活性的杂类化合物并对高活性的杂衍生物A进行构效关系研究,设计合成了38个3-(CH2)nCO2C2H5-1,5-苯并硫氮杂衍生物6和7(n=1,2),其结构经核磁共振波谱、质谱、红外光谱及元素分析等确证;并采用X射线单晶衍射技术测定了目标化合物的立体结构,发现其分子中的七元杂环是扭曲的船式构象.实验还考察了合成化合物的抑真菌活性,结果表明,当乙氧羰基烷基[(CH2)nCO2C2H5]在七元杂环的3位时杂的活性降低;将Lewis CeCl3.7H2O-NaI用于催化含硫化合物与α,β-不饱和酮的迈克尔加成反应,发现该催化剂能有效促进高位阻α,β-不饱和酮与邻氨基苯硫酚的迈克尔加成;同时研究了中间体5的分子内缩合反应,发现TiCl4是合成Schiff碱非常有效的促进剂.     

DABCO-based ionic liquids:Green and efficient catalysts with a dual catalytic role for aza-Michael addition

Four recoverable and reusable ionic liquids based on 1,4-diazobicyclo[2.2.2]octane(DABCO) have been synthesized to catalyze the aza-Michael addition of secondary amines to a,b-unsaturated compounds.Among the catalysts tested,[DABCO-PDO][OAc] was found to be most suitable for the reaction of a wide range of cyclic substrates without any solvent at room temperature,and afford the products in good to excellent yields within an appropriate amount of time.The proposed mechanism for the dual activation of the catalyst was supported by experimental results as well as the DFT calculation.In addition,the ionic liquids used can be regenerated and recycled several times without any loss of activity.     

A bifunctional rosin-derived thiourea catalyzed asymmetric tandem reaction and its new mechanism

A direct asymmetric tandem reaction of a-nitro ketones with b g-unsaturated a-ketoesters was found to be catalyzed by a bifunctional rosin-derived thiourea and gave 5-nitro-2-actoxyl-2-pentenates in excellent ee values and yields,a much better result than previously reported.Furthermore,through theoretical analysis,literature research and experimental verifications,a new mechanism involving an inverse-electron-demand Diels–Alder(IEDDAR) and a retro-Henry reaction was proposed.     

Hβ/MCM-41复合分子筛催化剂上苯甲醚与乙酸酐酰化反应研究

以β沸石为硅源,制备了不同硅铝比的Hβ/MCM-41复合分子筛,考察了该复合分子筛对苯甲醚与乙酸酐酰化反应的催化效果,并与介孔MCM-41、微孔Hβ分子筛的催化效果进行了比较,研究了分子筛硅铝比、酸性及孔道结构对酰化反应催化性能的影响。结果表明,对于苯甲醚和乙酸酐酰化反应,Hβ/MCM-41复合分子筛具有较好的催化稳定性,反应过程中的积炭量较少,积炭的碳氢比较低。该复合分子筛不仅具有微孔沸石的强酸性,而且具有较大孔径的介孔,产物分子能及时从孔道中扩散出来,催化活性位不易中毒失活。