有机硅核-壳型聚丙烯酸酯乳液的合成及油田固砂性能研究

有机硅核-壳型聚丙烯酸酯乳液的合成及油田固砂性能研究;聚丙烯酸酯乳液;有机硅改性;固砂;渗透率     

4-二甲基氨基吡啶催化合成N-保护氨基酸三氟乙酯

合成了6个未见文献报道的N-保护氨基酸三氟乙酯。4-二甲基氨基吡啶对N-保护氨基酸三氟乙酯的合成具有较高的催化活性,使三氟乙酯的合成产率大大增加。     

有机硅聚丙烯酸酯微乳液的合成与性能

有机硅聚丙烯酸酯微乳液的合成与性能;硅氧烷     

α-亚胺酯不对称加成合成手性α-氨基酸衍生物的研究进展

手性α-氨基酸衍生物在生命医药、精细化工等领域的广泛应用极大地促进了其合成方法的发展.目前在众多合成手性α-氨基酸衍生物的方法中,α-亚胺酯的不对称亲核加成反应是合成手性α-氨基酸衍生物的有效方法之一,成为不对称催化研究的热点.从反应类型和亲核试剂类型的角度出发,总结了α-亚胺酯不对称亲核加成反应合成手性α-氨基酸衍生物的研究进展.具体介绍了α-亚胺酯的烯丙基化反应、芳基化反应、Mannich反应、烯基化反应、炔基化反应及烷基化反应等六种合成手性α-氨基酸衍生物的主要方法以及相应反应机理及发展现状,并对合成手性α-氨基酸衍生物的发展方向进行了展望.     

有机硅氧烷嵌段共聚物的合成及表征

以不同分量的α,ω-双(γ-氨丙基)聚二甲基硅氧烷预聚物为软段,分别以聚芳 酯、聚酰亚胺为硬段合成了嵌段长短不同及含量不同的聚有机硅氧烷-聚芳酯嵌段共聚物和聚有机硅氧烷-聚酰亚胺嵌段共聚物。     

固-液相转移催化合成 Ⅳ.α-甲基丝氨酸及其它氨基酸

利用活化了的氨基酸酯,通过烷基化反应合成α-氨基酸是近年来使用的简便方法。特别是以苯甲醛与简单的氨基酸酯反应生成的Schiff碱为底物,用固-液相转移催化烷基化反应合成a-氨基酸,不仅条件温和,而且操作简便,原料易得,选择性好。我们采用上述方法成功地合成了α-甲基     

氨基酸5—氟尿嘧啶酯类衍生物的合成及其抗肿瘤活性研究

用氨基酸作抗癌药物载体以提高对癌细胞选择性的研究引起了人们的浓厚兴趣。在前文中,我们报道了5-氟尿嘧啶乙酰和丙酰氨基酸及其氨基酸的3-(N′-5-氟尿嘧啶基)-丙醇酯的合成及其抗肿瘤试验研究。本文将报道一系列氨基酸(5-氟尿嘧啶-1,3-双丙基)酯盐酸盐的合成及其体外抗肿瘤活性的研究。 合成路线如下:     

N-(5-氯-2-羟苄基)氨基酸酯的合成、表征及抑菌活性

以5-Cl水杨醛和L-苯丙氨酸、L-亮氨酸及L-甘氨酸的脂肪酸酯为原料,通过碱催化的席夫碱缩合反应,合成了6种N-(5-氯-2-羟苄基)席夫碱氨基酸酯及其还原产物N-(5-氯-2-羟苄基)氨基酸酯。化合物的结构及组成经过IR、1HNMR和元素分析测试技术进行了表征。合成的席夫碱及其还原产物对革兰氏阴性菌、革兰氏阳性菌及真菌均有不同程度的抑制作用。质量分数为0.01%的N-(5-氯-2-羟苄基)席夫碱氨基酸酯对大肠杆菌的抑菌率达90%以上,而N-(5-氯-2-羟苄基)氨基酸酯对金黄色葡萄球菌的抑菌率也在90%以上,均为强抑菌活性,其中N-(5-氯-2-羟苄基)苯丙氨酸酯的抑菌率达98%以上。     

磷酰化氨基酸酯的合成、波谱表征及生物活性

磷酰化氨基酸及其酯属于磷酰胺类, 它们作为天然氨基酸的含磷类似物, 具有良好的生物活性, 它的合成与性质的研究引起人们的浓厚兴趣. 本工作用亚硫酰氯先合成磷酰化酰氯, 再由其与氨基酸甲酯反应合成了一系列磷酰化氨基酸酯, 产物经红外光谱, 核磁共振氢谱、碳谱、磷谱, 质谱及元素分析鉴定, 并初步研究这些化合物的抗菌与抗肿瘤的生物活性.     

2-(N-三氟乙酰-N-三甲基硅烷基)氨基-3-三甲基硅烷氧基-羧酸三甲基硅烷酯和2-(N-三氟乙酰)-2,3-脱氢氨基酸的合成

利用三氟甲基磺酸三甲基硅烷酯, 我们合成了一种新的、化学活性很高的合成中间产物2-(N-三氟乙酰-N-三甲基硅烷基)氨基-1, 1-二(三甲基硅烷氧基)乙烯。脂肪醛或芳香醛发生碳碳成键的加成反应, 生成β碳原子上带有易离去基团三甲基硅烷氧基、N原子上带有保护基团三氟乙酰基的α氨基酸三甲基硅烷酯。消除反应得到了一个合成α、β脱氢氨基酸的可行途径。这类化合物是合成复杂多肽和肽生物碱的基元物。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.