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.     

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.     

甲氧羰基亚甲基三苯基胂与邻羟基芳醛,酮的反应-5,6-苯并-2-吡喃酮的合成

本文报道一种合成烃基取代5,6-苯并-2-吡喃酮的方法。甲氧羰基亚甲基三苯基胂与烃基取代的邻羟基芳醛、酮反应,首先生成α,β-不饱和酸酯,继而发生分子内环化,生成烃基取代的5,6-苯并-2-吡喃酮。     

手性氮杂卡宾金属络合物的合成及其在不对称催化反应中的应用

手性氮杂卡宾金属络合物在多种催化反应中得到了广泛的应用, 并取得了很好的研究成果. 综述了手性氮杂卡宾金属络合物的合成以及它们在催化不对称反应中的应用研究进展, 如催化α,β-不饱和酮的1,4-加成反应、酮的氢硅烷化反应、烯烃的氢化反应和烯烃的复分解反应等.     

去氧亚甲基霉素A的合成

本工作发现了一个烯丙基硅烷的铜催化选择性氧化反应并研究了锂铜试剂对氧化产物β三甲基硅取代的α、β-不饱和酮的共轭加成反应。 通过上面这些反应,利用重要的和潜在多功能的中间体2,合成了去氧亚甲基霉素A,1。另外给出了一个合成亚甲基霉素B,3的新方法。     

取代吡唑啉衍生物的合成与生物活性

采用α-三唑-β-烷氧基芳酮与肼关环,制备了1,3-二苯基-4-三唑基吡唑啉1a,1-苯基-3-对氯苯基-4-三唑基吡唑啉1b和3-取代苯基-4-三唑基吡唑啉(7),并研究了化合物7的成环优化条件.使用α,β-不饱和酮与肼关环合成了1,3,4,5-多取代吡唑啉衍生物1c-1h,并初步用质谱法确定了该反应产物的结构;同时,以3,5-二取代吡唑啉(6)和7作为中间体合成了1-,3-,4-或5-取代的化合物2a-2l.初步生物活性测定结果表明,所合成的化合物均有一定的杀菌、激素和除草效果.     

含硫碳负离子的反应和应用研究(Ⅶ)——4,4-二取代1,7-二官能团化合物的合成

通过α-芳基磺酰基乙酸乙酯与α,β-不饱和酯、腈、酮在温和条件下进行双共轭加成反应一锅法高产率地合成了一系列1,7-二官能团化合物,对它们的结构作了表征,初步讨论了Michael受体、相转移催化剂和溶剂对该双共轭加成反应的影响。     

1-(SR)-对甲苯亚磺酰基-3-戊烯-2-酮与环戊二烯的不对称催化环加成反应

前文曾报道了α-苯磺酰基-α,β-不饱和酮作为双烯体和亲双烯体所进行的不对称催化HeteroDiels-Alder反应^[1]和Diels-Alder反应^[2].为深入研究其反应机理,提出反应过渡态模型和鉴定环加成物构型.     

席夫碱修饰的MCM-41介孔分子筛与碳酸钾共同催化查尔酮的环氧化反应

将介孔分子筛MCM-41依次与3-氯丙基三乙氧基硅烷、二氨基硫脲和水杨醛反应,得到席夫碱修饰的介孔分子筛MCM-41催化剂,以过氧化氢为氧源,研究了其与K2CO3共同催化α,β-不饱和酮的环氧化反应。 化合物的结构经1H NMR和IR分析确认。 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,室温下α,β-不饱和酮的环氧化反应在短时间内均以较高的产率(最高达93%)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4次,仍能以较高产率得到环氧化产物。     

铑-ImiFerroPhos配合物对β-取代-α,β-不饱和磷酸酯的不对称氢化

将手性二茂铁双膦配体ImiFerroPhos应用到β-取代-α,β-不饱和磷酸酯的不对称氢化反应中,在温和的反应条件下,以高收率及较高对映选择性合成了一系列β-取代的手性磷酸酯,最高获得了92%的ee值.     

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.     

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.     

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     

Asymmetric catalyzed intramolecular aza-Michael reaction mediated by quinine-derived primary amines

An intramolecular organocatalytic enantioselective aza-Michael reaction of carbamates, sulfonamides and acetamides to a,b-unsaturated ketones was developed. This process is promoted by 9-amino-9-deoxy-epi-quinine and diphenyl hydrogen phosphate to afford a straightforward and expeditious synthesis of several synthetically useful five-and six-membered heterocycles with excellent enantioselectivity(92%–97.5% ee) and very good yields(up to 99%).     

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。     

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.     

Enzyme-catalyzed asymmetric domino aza-Michael/aldol reaction for the synthesis of 1,2-dihydroquinolines using pepsin from porcine gastric mucosa

An unprecedented enzyme-catalyzed asymmetric domino aza-Michael/aldol reaction of 2-aminobenzaldehyde and a,b-unsaturated aldehydes is achieved. Pepsin from porcine gastric mucosa provided mild and efficient access to diverse substituted 1,2-dihydroquinolines in yields of 38%–97% with 6%–24%enantiomeric excess(ee). This work not only provides a novel method for the synthesis of dihydroquinoline derivatives, but also promotes the development of enzyme catalytic promiscuity.     

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.