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1.
以3-乙基-3-羟甲基氧杂环丁烷为原料,与甲基磺酰氯磺酰化,得到3-乙基-3-甲磺酰基甲基氧杂环丁烷;在碱性条件下,以PEG600作相转移催化剂,用3-乙基-3-甲磺酰基甲基氧杂环丁烷与乙二醇醚化得到2-[(3-乙基-3-氧杂环丁基)甲氧基]乙醇;然后与甲基丙烯酸甲酯进行酯交换得到目的产物2-[(3-乙基-3-氧杂环丁烷)甲氧基]甲基丙烯酸乙酯。3-乙基-3-羟甲基氧杂环丁烷与3-溴丙烯反应,生成3-乙基-3-[(2-丙烯-1-基氧基)甲基]氧杂环丁烷,然后在氯铂酸的催化下,与三乙氧基硅烷反应得到3-乙基-3-[[3-(三乙氧基硅)丙氧基]甲基]氧杂环丁烷。产物经红外光谱和核磁共振谱表征得到确证。  相似文献   

2.
利用荧光浓度指示剂fura-2研究稀土离子的跨膜行为   总被引:6,自引:0,他引:6  
本文提出了利用fura-2测量细胞内游离稀土离子浓度的定量方法。实验结果表明, 在模拟细胞内离子组成的条件下, 稀土离子La^3^+和Y^3^+与fura-2形成1:1的配合物。其配合物的表观离解常数分别为161nmol.dm^-^3和404nmol.dm^-^3,pH7.05, 有未配对f电子的Nd^3^+, Ho^3^+, Sm^3^+, Dy^3^+,Ce^3^+, Yb^3^+等稀土离子对荧光起萃灭作用。此性质使我们能够定性鉴定它们是否进入了细胞。我们使用如上性质, 利用单细胞阳离子测试系统, 以小鼠骨髓瘤细胞为模式细胞, 研究了上游离稀土离子的跨膜行为及部分体内小分子对稀土离子跨膜行为的影响。实验结果支持游离稀土离子不能通过细胞膜的假设, 而且所研究的体内小分子在生理浓度下对稀土离子的跨膜也无明显作用。  相似文献   

3.
La3+或Eu3+与微过氧化物酶-8相互作用强弱的研究   总被引:1,自引:0,他引:1  
研究了La3+或Eu3+与微过氧化酶-8(MP-8)相互作用并比较了它们与MP-8相互作用的强弱. 紫外-可见(UV-Vis)吸收光谱和电化学的结果表明, 不论在不含NaCl或含NaCl的溶液中,一个La3+或Eu3+优先与MP-8分子中血红素上两个丙酸基中的羧基氧发生强的键合作用,而过量的La3+或Eu3+与肽链上的羰基氧发生弱的相互作用.实验结果还清楚地证明Eu3+与MP-8的相互作用要强于La3+与MP-8的相互作用.  相似文献   

4.
The reaction of 2-phenyl- and 1-methyl-2-phenylindole with nitrogen dioxide or with nitrous acid (NaNO2-CH3COOH) in benzene leads mainly to the formation of the isonitroso and 3-nitroso indole derivatives, respectively. When reacted with nitrous acid, 1-methyl-2-phenylindole gives also the corresponding azo-bis-indole in good yields. The reaction of indole with nitrogen dioxide leads to 2-(indol-3-yl)-3H-indol-3-one as the main product together with small amounts of 2-(indol-3-yl)-3H-indol-3-oxime; whereas the major product obtained when the same indole is reacted with nitrous acid is represented by 2-(indol-3-yl)-3H-indol-3-oxime. The reaction of 3-alkyl substituted indoles with nitrogen dioxide is rather complex and results in the formation of different nitro indoles, whereas nitrosation is observed when nitrous acid is used. Crystal structures of 2-(indol-3-yl)-3H-indol-3-one and of 4-nitro-N-acetyltryptamine have been determined by X-ray analysis.  相似文献   

5.
Interaction of 6-chloropurine 3-oxide with several amines led to 6-substituted purine 3-oxides. 6-Chloropurine 3-oxide and selenourea gave 6-selenopurine 3-oxide. 6-Mereaptopurine 3-oxide, prepared from the 6-chloro derivative and ammonium dithioearbonate, was transformed with chlorine and hydrogen fluoride into 6-purinesulfonyl fluoride 3-oxide which upon ammonolysis afforded purine-6-sulfonamide 3-oxide. Methanelhiol and 6-ehloropurint: 3-oxide yielded the known 6-methylthiopurine 3-oxide, which by treatment with chlorine was oxidized to 6-methyl-sulfonylpurine 3-oxide. Reaction of the latter with hydroxylamine led to an improved synthesis of 6-hydroxylaminopurine 3-oxide, which by interaction with manganese dioxide was transformed into 6-nitrosopurine 3-oxide.  相似文献   

6.
Four kinds of polythiophenes have been doped with CH3SO3H in CHCl3 under air,oxygen,and nitrogen. In the doping of two types of poly(3-hexylthiophene)s,P3HexTh(Zn/Ni)and P3HexTh(Fe)with different contents of a head-to-tail unit,the p-doping occurs at a similar rate.The reaction between poly(3-dodecylthiophene),P3DodTh,and the acid takes place more rapidly.P3OBuTh with a butoxy substituent undergoes more facile p-doping and receives photochemical reaction with CHCl3,and this reaction obeys a pseudo-first-order rate law with a rate constant kobs of 1.42×10-5s-1at room tempera- ture.  相似文献   

7.
Reactions of [La(AlMe4)3] and [Y(AlMe4)3] with PMe3 show that the phosphine can cleave Ln--CH3--Al linkages, separating Me3Al(PMe3). PMe3 (3 mol equiv) reacts with [Y(AlMe4)3] to give [(YMe3)n] contaminated with by-products containing phosphorus and aluminum. The La-based analog, [(LaMe3)n], is not formed selectively from the reaction of [La(AlMe4)3] with PMe3 or Et2O, which rather yields insoluble La/Al heterobimetallic products. Three multi-nuclear La-based clusters were obtained from a reaction of [La(AlMe4)3] with PMe3 (1 equiv) and identified by X-ray structure analyses. Each cluster exhibits extensive methyl group degradation and contains methylene, methine, or carbide moieties. [La4Al8(CH)4(CH2)2(CH3)20(PMe3)] has a [La4(CH)4] cuboid core supported by AlMe3, Me2AlCH2AlMe2, and PMe3 ligands. [La4Al8(C)(CH)2(CH2)2(CH3)22(toluene)] also contains a cuboid core, [La3Al(C)(CH)2(CH2)], which includes one exo cubic lanthanum atom, and is supported by AlMe3, Me3AlCH2AlMe2, (AlMe4)-, and toluene ligands. The lanthanum atoms in [La5Al9(CH)6(CH3)30] are arranged in a trigonal bipyramidal fashion with (CH) functionalities capping each face. The [La5(CH)6]3- core is formally balanced by three AlMe2 + moieties and is additionally supported by six AlMe3 ligands. The unit cell contains two independent La5 clusters, one with pseudo-C3h and the other with pseudo-D3 symmetry, as well as two molecules of the separation co-product Me3Al(PMe3).  相似文献   

8.
Nitration of 3-substituted-4-hydroxy-2(1H)-quinolones 1 with nitric acid leads either to 3-nitro- 2 or 3-hydroxyquinolinediones 3 , depending on the reaction conditions. 3-Substituted-3-hydroxyquinolinediones 3 are also obtained by oxidative hydroxylation with peracetic acid. Amination of 3-substituted-3-chloroquinolinediones 4 with ammonium hydroxide predominantly leads again to 3-substituted-3-hydroxyquinolinediones 3 , only in one case the 3-aminoquinolinedione 5 could be isolated. With morpholine or pyridine as amines the expected 3-aminoquinolinediones 6 and 7 were obtained.  相似文献   

9.
NMR chemical shifts of 1H, 13C, and 73Ge are reported for a series of monosubstituted aromatic trimethylgermanes of the type XC6H4Ge(CH3)3; X = p-N(CH3)2, p-OCH3, p-OC2H5, p-C(CH3)3, p-Si(CH3)3, p-Ge(CH3)3, p-Sn(CH3)3, p-CH3, m-CH3, -H, m-OCH3, p-Cl, p-Br, m-F, m-CF3, p-CF3, o-OCH3, and o-CH3. The relatively narrow 73Ge resonances show a strong correlation with Hammett sigma constants, with a correlation coefficient of 0.976 and 0.876 for 73Ge chemical shifts in meta- and para-substituted derivatives, respectively. The 13C chemical shifts of the methyl carbons bonded to germanium also display a relationship, with correlation coefficients of 0.904, 0.993, and 0.911 for para-, meta- and all derivatives, respectively. Comparisons of the Hammett plots for the homologous series XC6H4M(CH3)3; M = C, Si, Ge, Sn, show that, in general, correlation coefficients decrease while slopes increase significantly down the group, presumably reflecting the corresponding increase in chemical shift range of the group 14 atom. The Hammett constant derived for the p-Ge(CH3)3 group of +0.13 compares with the NMR-derived constants of -0.12 for p-C(CH3)3, +0.14 for p-Si(CH3)3, and -0.14 for p-Sn(CH3)3. The indication of electron release by carbon and tin can be rationalized through traditional hyperconjugative arguments for carbon and by the low electronegativity and consequent inductive effect of tin. The small electron attraction suggested by the positive constants for silicon and germanium can be simply, and perhaps naively, attributed to pi-acceptor interactions with the benzene ring.  相似文献   

10.
改性纳米碳酸钙-聚丙烯复合材料的结构与性能研究   总被引:2,自引:0,他引:2  
制备了硬脂酸钙包覆的纳米碳酸钙( CaSt-nano-CaCO3),并采用熔融共混的方法制备出iPP/CaStnano-CaCO3和iPP/nano-CaCO3复合材料.与纯iPP相比,复合材料的弯曲强度和弯曲模量随着CaCO3粒子含量的增加而提高,冲击性能也得到改善.相对于iPP/nano-CaCO3,iPP/CaS...  相似文献   

11.
3-Chloro-2-phenyl-6-p-tolyl and 3-chloro-2,6-di-p-tolyl-4H-thiopyran-4-ones have been synthesized in moderate yieldes from the reaction of 3-chloro-tetrahydrothiopyran-4-ones with phosphorus pentachloride. Their thiones, oximes, and hydrazones have been also prepared. Treatment of thiones with malononitrile gave the corresponding 3-chloro-4-thiopyrylidenemalononitriles which gave 3-chloro-spirothiopyran derivatives of pyrazole, isoxazole, 1,3-thiazines when treated with hydrazine hydrate, hydroxylamine hydrochloride, thiourea and thiosemicarbazide, respectively. While treatment of 3-chloro-thiopyrylidene-malononitriles with acetylacetone gave the corresponding 3-chloro-spirothiopyran derivatives of pyran.  相似文献   

12.
铬在纳米晶氧化铁中的掺杂研究   总被引:1,自引:0,他引:1  
Fe^3^+(Cr^3^+)/Fe^2^+混合离子(M^3^+/M^2^+原子比为2:1)共沉淀法制备的Cr~2O~3掺杂量O~14%(质量分数)系列纳米氧化铁,XRDRietveld分析表明全是晶态γ-Fe~2O~3和非晶Fe~2O~3的混合物。非晶丰度范围为21.72%~48.6%。Mossbauer谱分析发现,掺杂量少于2%(质量分数)的氧化铁,晶态和非晶态均是磁性六线谱,大于2%(质量分数)后,另出现强度随掺杂量增加线性递增的超顺磁二线谱。共沉淀过程中,Fe^3^+为主夹杂定量Cr^3^+的Fe^3^+水合配合物网络与Cr^3^+为主夹杂定量Fe^3^+的Cr^3^+水合配合物网络,是形成磁性氧化铁和非晶非磁氧化铁的基础,后者镶嵌在前者中间,阻碍其晶化和晶粒长大,自身形成非晶非磁含铬氧化铁。  相似文献   

13.
制备和表征了三种新型质子酸离子液体: 吗啡啉硫酸氢盐([Hnhm]HSO4)、4-甲基吗啡啉硫酸氢盐 ([Hnmm]HSO4)和SO3H-功能化的4-(3-磺丙基)吗啡啉硫酸氢盐([C3SO3Hnhm]HSO4). 以氯乙酸(CAA)和乙醇合成氯乙酸乙酯的酯化反应考察了它们的酸性和催化活性, 并与1-(3-磺酸基)丙基-3-甲基咪唑硫酸氢盐、1-(3-磺丙基)吡啶硫酸氢盐、1-(3-磺丙基)-2-吡咯烷酮硫酸氢盐等三种具有不同氮杂环的SO3H-功能化酸性离子液体以及浓硫酸相对照. 结果表明, 上述SO3H-功能化离子液体对酯化反应的催化性能比非SO3H-功能化的[Hnhm]HSO4和[Hnmm]HSO4都高, 等同甚至优于浓硫酸. 当反应条件为: n(EtOH)∶n(CAA)∶n([C3SO3Hnhm]HSO4)=1.3∶1∶0.2, 反应温度80 ℃, 反应时间3 h, 酯收率可达93.4%. 而且离子液体经真空干燥重复使用9次, 催化活性仍无明显下降. 以[C3SO3Hnhm]HSO4催化乙酸和不同醇的酯化反应获得较高的酯收率和选择性, 离子液体跟酯产物均能自动分相. 还考察了SO3H-功能化酸性离子液体对奥氏体316不锈钢的腐蚀性. 尽管SO3H-功能化离子液体与硫酸的酸性相近, 但对钢试样的腐蚀率不到硫酸的1/3.  相似文献   

14.
测定了MoO3/γ-Al2O3、MoO3/TiO2、MoO3/SiO2的激光Raman谱. 通过MoO3/γ-Al2O3、MoO3/TiO2在吡啶吸附前后、氨水提取前后的谱图对比说明, 单层分散的MoO3, 即特征峰为~950cm^-^1的"二维聚钼酸"中钼的配位状态不是单一的,其中一种表面含钼物种(Mo-1)不吸附吡啶, 不溶于氨水, 不显示较强的表面酸性; 另一种表面含钼物种(Mo-2)可吸附吡啶, 溶于氨水, 与催化剂的表面酸位密切相关. 我们认为Mo-1为四面体配位的钼; Mo-2为八面体配位的钼. MoO3/SiO2中的MoO3能100%被氨水溶去, 其酸位数与表面Mo^6^+数之比接近1, 是由其中Mo-2的比例较高, 载体与活性组分之间的相互作用较弱这两个因素所造成的。  相似文献   

15.
This research constitutes an operational test to assess the influence of platinum-attached phosphine ligands in the formation process of "open-face" TlPt3 or "full" Pt3TlPt3 sandwich clusters. Accordingly, the reaction of TlPF6 with triphenylphosphine Pt4(mu2-CO)5(PPh3)4, under essentially identical boundary conditions originally used to prepare (90% yield) the triethylphosphine "full" Pt3TlPt3 sandwich, [(mu6-Tl)Pt6(mu2-CO)6(PEt3)6]+ (3) ([PF6]- salt), from Pt4(mu2-CO)5(PEt3)4 was carried out to see whether it would likewise afford the unknown triphenylphosphine Pt3TlPt3 sandwich analogue of or whether the change of phosphine ligands from sterically smaller, more basic PEt3 to PPh3 would cause the product to be the corresponding unknown triphenylphosphine "open-face" TlPt3 sandwich that would geometrically resemble the known bulky tricyclohexylphosphine [(mu3-Tl)Pt3(mu2-CO)3(PCy3)3]+ sandwich (2a). Both the structure and composition of the resulting "open-face" sandwich product, [(mu3-Tl)Pt3(mu2-CO)3(PPh3)3]+ (1a) ([PF6]- salt), were unequivocally established from a low-temperature CCD X-ray crystallographic determination. The calculated Pt/Tl atom ratio (3/1) of 75%/25% is in excellent agreement with that of 72(3)%/28(5)% obtained from energy-resolved measurements on a single crystal with a scanning electron microscope. Crystals (80% yield) of the orange-red were characterized by solid-state/solution IR and variable temperature 205Tl and 31P{1H} NMR spectra; the 31P{1H} spectra provide convincing evidence that is exhibiting dynamic behavior at room temperature in CDCl3 solution. The corresponding new "open-face" (mu3-AuPPh3)Pt3 sandwich, [(mu3-AuPPh3)Pt3(mu2-CO)3(PPh3)3]+ (1b) ([PF6]- salt), was quantitatively obtained from by reaction with AuPPh3Cl and spectroscopically characterized by IR and 31P{1H} NMR spectra. A comparative geometrical evaluation of the observed steric dispositions of the platinum-attached PR3 ligands in the "open-face" (mu3-Tl)Pt3 sandwiches of (with PPh3) and the known (with PCy3) and in the known "full" Pt3TlPt3 sandwich of (with PEt3) along with the considerably different observed steric dispositions of the PR(3) ligands in the known "open-face" (mu3-AuPCy3)Pt3 sandwich of (with PCy3) and in the known "full" Pt3AuPt3 sandwich of (with PPh(3)) has been performed. The results clearly indicate that, in contradistinction to the known triphenylphosphine Pt3AuPt3 sandwich of , PPh3 and bulkier PCy3 ligands of Pt3(mu2-CO)3(PR3)3 units are sterically too large to form "full" Pt3TlPt3 sandwiches. In other words, the nature of the thallium(I) sandwich-product in these reactions is sterically controlled by size effects of the phosphine ligands. Comparative examination of bridging carbonyl IR frequencies of and with those of closely related "open-face" and "full" sandwiches provides better insight concerning the relative electrophilic capacities of Tl+, Au+, and [AuPR3]+ components in forming sandwich adducts with Pt3(mu2-CO)3(PR3)3 nucleophiles.  相似文献   

16.
IntroductionThelundnescenceofrare-earth-dopedcompoundshasbeenstudiedextensivelyduringthelastdecade,especiallyontrivalentceriumandterbiumandontheenergytransferbetweentheseionsl'2'3.Thegreen-emittingphosphorousarecerium-sensitizedterbiummaterials,themostwidelyusedoneisCe,.,,Tb,,,MgAl,,O,,'.However,thealuminiumfamilyrequireshightemperaturesfortheirsynthesis.Investigationswere,therefore,focusedonloweringthepreparativetemperatures.Thephosphatefamily,forexample,(La,Ce,Tb)PO"",needsalowerprepara…  相似文献   

17.
The mechanical properties, such as Young's modulus, yield strength, and the elongation at breakage, were investigated for several sulfur-containing biopolymers P(3HB-co-3MP). A series of P(3HB-co-3MP) samples with 3MP unit content ranging from 6.6 to 39.1 mol-% was biosynthesized by fermentation using the PHA-synthesizing bacteria Cupriavidus necator. For comparison, the bacterially synthesized P(3HB) and P(3HB-co-3HP) with the 3HP unit content ranging from 13.1 to 21.1 mol-% were also investigated. It was found that the sulfur-containing P(3HB-co-3MP) is much more durable to stretching. Notably, P(3HB-co-3MP) with the 3MP unit content of only 6.6 mol-% was found to show excellent mechanical properties.  相似文献   

18.
Bi3+敏化的SrSiO3:Eu3+,Bi3+发光体的合成与发光   总被引:2,自引:0,他引:2  
本文采用高温固相扩散法合成出一种新的发光体SrSiO3:eU^3^+,Bi^3^+。研究了激活剂Eu^3^+与敏化剂Bi^3^+浓度变化与发光强度的关系。实验发现,组成为Sr0.817Li0.0915SiO3:Eu^3^+0.075,Bi^3^+的发光体其发光强度最大。给出了发光体SrSiO3:Eu^3^+,SrSiO3:Eu^3^+,Bi^3^+的激发光谱与发光光谱;测定了发光体的X射线粉...  相似文献   

19.
This work presents the substituent effects on the 1H and 13C NMR chemical shifts in the cis-isomer of 3-Y-cyclohexanols (Y = Cl, Br, I, CH3, N(CH3)2 and OCH3) and 3-Y-1-methoxycyclohexanes (Y = F, Cl, Br, I, CH3, N(CH3)2 and OCH3). It was observed that the H-3 chemical shift, due to the substituent alpha-effect, increases with the increase of substituent electronegativity when Y is from the second row of the periodic table of elements, (CH3 *sigma(C3--H3a) interaction energy. This interaction energy, for the halogenated compounds, decreases with an increase in size of the halogen, and this is a possible reason for the largest measured chemical shift for H-3 of the iodo-derivatives. The beta-effect of the analyzed compounds showed that the chemical shift of hydrogens at C-2 and C-4 increases with the decrease of n(Y) --> *sigma(C2-C3) and n(Y) --> *sigma(C3-C4) interaction energies, respectively, showing a behavior similar to H-3. The alpha-effect on 13C chemical shifts correlates well with substituent electronegativity, while the beta-effect is inversely related to electronegativity in halogenated compounds. NBO analysis indicated that the substituent inductive effect is the predominant effect on 13C NMR chemical shift changes for the alpha-carbon. It was also observed that C-2 and C-4 chemical shifts for compounds with N(CH3)2, OCH3 and F are more shielded in comparison to the compounds having a halogen, most probably because of the larger interaction of the lone pair of more electronegative atoms (n(N) > n(O) > n(F)) with *sigma(C2-C3), *sigma(C3-C4) and *sigma(C3-H3a) in comparison with the same type of interaction with the lone pair of the other halogens.  相似文献   

20.
Extraction chromatography with commercially available UTEVA resin (for uranium and tetravalent actinide) was applied for the separation of Th and U from control solutions prepared from a multi-element control solution and from sample solutions of solidified simulated waste. Thorium and U in control solutions with 1-5mol/dm(3) HNO(3) were extracted with UTEVA resin and recovered with a solution containing 0.1mol/dm(3) HNO(3) and 0.05mol/dm(3) oxalic acid to be separated from the other metallic elements. Extraction behavior of U in the sample solutions was similar to that in the control solutions, but extraction of Th was dependent on the concentration of HNO(3). Thorium was extracted from 5mol/dm(3) HNO(3) sample solutions but not from 1mol/dm(3) HNO(3) sample solutions. We conjecture that thorium fluoride formation interferes with extraction of Th. Addition of Al(NO(3))(3) and Fe(NO(3))(3), which have higher stability constant with fluoride ion than Th, does improve extractability of Th from 1mol/dm(3) HNO(3) sample solution.  相似文献   

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