Synthesis,crystal structure and spectroscopic properties of a copper(II) complex of the Schiff-base derived from picolinaldehyde N-oxide and 4-aminoantipyridine

The Schiff-base (PNOAAP) derived from picolinaldehyde N-oxide and 4-aminoantipyrine, and its copper(II) complex: [Cu(PNOAAP)₂(EtOH)₂]₂(ClO₄)₄ (1) has been prepared and characterized by elemental analysis, i.r., ¹H-n.m.r. spectrum, and single crystal X-ray crystallographic determination. The PNOAAP ligand isomerizes from trans to cis after chelating to copper(II).     

SiO2／LaF3：Eu3＋核壳结构发光粒子的制备与表征

采用简单的液相法合成了SiO2/LaF3:Eu3 核壳结构发光粒子,并对其结构及发光性能进行了表征.XRD分析表明包覆层LaF3:Eu3 为立方晶相结构,红外光谱表明SiO2颗粒表面有柠檬酸的修饰,电镜照片表明合成了球形的核-壳结构的复合粒子,包覆层厚度为10～20 nm,光谱测试表明核-壳复合粒子与纯的LaF3:Eu3 具有相同的发光性能,均以589 nm附近的5D0-7F1磁偶极跃迁为最强发射峰,说明Eu3 在LaF3基质中占据的格位相同.     

Aqueous biphasic hydroformylation of higher alkenes and highly efficient catalyst recycling in the presence of a polar low boiling solvent

The hydroformylation of higher alkenes under aqueous biphasic reaction conditions with a rhodium catalyst derived from BISBIS (sodium salt of sulfonated 2,2′-bis (diphenylphosphinomethyl)-1,1′-biphenyl) in the presence of a polar low boiling point solvent was studied. The addition of ethanol greatly accelerated hydroformylation, such that the turnover frequency (defined as the moles of converted alkene per mole of Rh per hour) and the selectivity for linear aldehyde were up to 2095 h^?1 and 99 %, respectively. The catalytic system could be recycled for at least five runs without significant loss of activity in the aqueous biphasic hydroformylation of 1-octene; the rhodium content leaching in product mixtures detected by inductively coupled plasma atomic emission spectroscopy was < 0.1 ppm.     

(1S,2S)-DPEN修饰的3%Ir/SiO2/2TPP催化苄叉丙酮的不对称加氢

在温和的条件下制备了负载型3%(w)Ir/SiO2/2TPP(三苯基膦)催化剂, 并且考察了(1S,2S)-1,2-二苯基乙二胺[(1S,2S)-DPEN]作为手性修饰剂对其催化苄叉丙酮不对称加氢反应性能的影响. 结果表明, 手性修饰剂(1S,2S)-DPEN的加入, 对苄叉丙酮不对称加氢反应活性和C=O加氢的选择性都有很好的促进作用. 经优化条件, 在40 ℃下, LiOH浓度为0.375 mol·L-1的甲醇溶液中, 氢气压力为6 MPa, 反应8 h后, 苄叉丙酮的转化率大于99.0%, 对不饱和醇的选择性大于99.0%, 不饱和醇的对映选择性(ee)值达到48.1%.     

新型交联壳聚糖树脂的制备及其对苯甲酸的吸附行为研究

以壳聚糖为原料,甲醛为预交联剂,环氧氯丙烷为交联剂,通过反相悬浮交联法制备出新型壳聚糖树脂,并用红外光谱和扫描电镜对其结构进行表征.测定了不同温度下新制备树脂自水中吸附苯甲酸的等温线,计算了吸附过程的热力学参数.并用Freundlich方程对实验数据进行拟合,发现该方程适用于所研究的吸附体系.体系的热力学与吸附机理密切相关,当苯甲酸浓度较低时,吸附为放热过程,体系熵减少,降温有利于吸附;当苯甲酸浓度较高时,吸附为吸热过程,体系熵增加,升温有利于吸附.     

铑-双膦配合物的咬角效应对催化1-十二烯氢甲酰化反应的影响

研究了HRh(CO)(PPh₃)₃-双膦配体(BISBI，BDPX，BDNA和BINAP)体系在1-十二烯氢甲酰化反应中的催化性能。4种双膦配体具有不同的空间结构，因而有不同的咬角(bite angle)，它们与铑催化剂前体HRh(CO)(PPh₃)₃进行配体交换后，形成不同的催化活性物种。4种复合催化剂体系中，HRh(CO)(PPh₃)₃-BISBI(咬角为120°)对直链醛的形成具有很高的区域选择性，这可能是因为形成了有利于生成直链烷基-铑的ee构型催化活性物种，其它3种双膦配体与HRh(CO)(PPh₃)₃组成的复合催化剂体系区域选择性没有多少变化，是与它们具有较小的咬角有关(BINAP85°，BDPX90°，BDNA104°)。上述4种HRh(CO)(PPh₃)₃ -双膦体系与HRh(CO)(PPh₃)₃-PPh₃体系相比较，催化活性较低，这可能是因为双膦的螯合配位作用使催化活性物种较稳定 。     

稀土与N-对甲基苯磺酰甘氨酸和邻菲咯啉配合物的合成与晶体结构

Three new lanthanide complexes with the formulae [Eu2（TsGly）6（phen）2（H2O）2] （1）, [Ln（TsGly）2（phen）2-（H2O）2]C1·2H2O [Ln=Er（2a） and Yb （2b）, TsGly=N-p-tolylsulfonylglycinate, phen= 1,10-phenanthroline] were synthesized. Crystallographic data for 1： monoclinic, P21/n, a= 1.29791（16） nm, b= 1.9034（2） nm, c= 1.7596（2） nm,β=93.410（3）°, V=4.3394（9） nm^3, Z=4, R1 =0.0326, wR2=0.0771; and for 2b： triclinic, P1, a= 1.2674（2） nm, b= 1.4405（2） nm, c= 1.4809（3） nm, a= 113.256（3）°, β= 108.253（3）°, γ=94.739（3）°, V=2.2922（7） nm°3, Z=2, R1=0.0292, wR2=0.0669. X-ray diffractional analysis reveals that compound 1 adopts dinuclear structure with fourfold bridging TsGly ligands between the Eu（Ⅲ） centers, while compound 2b features an unusual mononuclear structure.     

Selective Hydrogenation of Avermectin Catalyzed by Iridium-Phosphine Complexes

A series of new iridium complexes, IrCl（COD）（TMOPP） （1） [COD=1,5-cyclooctadiene, TMOPP=tris（4- methoxyphenyl）phosphine], IrCl（COD）（TFMPP） （2） [TFMPP = tris（4-trifluoromethylphenyl）phosphine], IrCl（COD）（BDNA） （3） [BDNA= 1,8-bis（diphenylphosphinomethyl）naphthalene], IrCl（COD）（BISBI） （4） [BISBI= 2,2＇-bis（diphenylphosphinomethyl）biphenyl] and IrCl（COD）（BDPB） （5） [BDPB= 1,2-bis（diphenylphosphinomethyl）benzene], were synthesized and characterized by NMR spectra and elemental analyses. In order to obtain the relationships between complex structures and their catalytic properties, IrCl（COD）（DPPM） （6） [DPPM = bis（diphenylphosphino）methane], IrCl（COD）（DPPE） （7） [DPPE= 1,2-bis（diphenylphosphino）ethane], IrCl（COD）（DPPP） （8） [DPPP=1,3-bis（diphenylphosphino）propane] and IrCl（COD）（TPP） （9） [TPP=triphenylphosphine], were also synthesized according to the reported methods. The hydrogenation results showed that the low electronic density at the central metal was favorable to increase the catalytic activity for the hydrogenation of avermectin, but decrease the selectivity to ivermectin. The complex with a large chelating ring and a bulky chelating backbone would easily cause the cleavage of C-O bond in avermectin to give a byproduct avermectin aglycon.     

Modification mechanism of Sn for hydrogenation of p-chloronitrobenzene over PVP-Pd/γ-Al2O3

PVP-Pd (1.5 wt.%)/γ-Al₂O₃ was prepared and used as a catalyst for the hydrogenation of p-chloronitrobenzene (p-CNB) to form p-chloroaniline (p-CAN), so that a serious dehalogenation reaction was happened. However, the catalytic property of this catalyst was remarkably affected by some metal cationic additives. Especially, when Sn⁴⁺ was introduced into the reaction system, the activity of the catalyst was not only promoted, but the dehalogenation reaction was also greatly suppressed. The average rate of hydrogenation increased from 1.28 mol H₂/mol Pd s on PVP-Pd/γ-Al₂O₃ catalyst to 1.96 mol H₂/mol Pd s on the PVP-Pd-Sn⁴⁺/γ-Al₂O₃ catalyst (molar ratio of Pd to Sn = 1:1), and the selectivity for p-CAN increased from 66.8 to 96.6%. The dehalogenation reaction was completely restrained as the molar ratio of Sn⁴⁺ to Pd was up to 5. The great promotion role of Sn⁴⁺ could be owing to the interaction between Sn⁴⁺ and −NO₂ group of the substrate. The combination of Sn⁴⁺ with oxygen in −NO₂ increased the polarity of NO bond. The increase of the polarity of NO benefited the activated dihydrogen to attack the NO bond, and the hydrogenation was accelerated. At the same time, the increase of the polarity of NO bond caused the more lone pair electron of p orbital on chlorine atom to dislocate to phenyl ring, so CCl bond was strengthened and the polarity of CCl was weakened. Furthermore, these were unfavorable for the activated dihydrogen to attack CCl bond and the hydrogenation selectivity was greatly improved.     

两种含氨基吡啶衍生物铜(Ⅱ)配合物的合成和晶体结构

Copper(Ⅱ) complexes Cu(C₆H₆N₂)₂(ClO₄)₂ (1) and Cu₂(OAc)₄(C₅H₅ClN₂)₂ (2) with amino-pyridine deriva-tives ligands have been synthesized and characterized by elemental analysis and IR spectrum. Their crystal struc-tures are determined by X-ray diffraction method. Compound 1， C₁₂H₁₆C₁₂CuN₄O₈， M_r=478.73， triclinic， space group ， a=0.7641(1)nm， b=0.7987(1)nm， c=0.7990(1)nm， α=106.78(1)°，β=95.71(1)°， γ=108.85(1)°， V=0.4317(1)nm³， Z=1， D_c=1.841g·cm^-3， μ=1.627mm^-1， F(000) =243，R₁=0.0264， ωR₂=0.0641 (I>2σ(I)). In 1， the center metal ion Cu(Ⅱ) possesses distorted octahedral geometry. Compound 2， C₁₈H₂₂C₁₂Cu₂N₄O₈， M_r=620.38，monoclinic， space group C2/c， a=1.9888(3)， b=0.9158(1)， c=1.4241(2)nm， β=115.89(1)°， V=2.3336(5)nm³， Z=4， D_c=1.766mg·cm^-3， μ=2.104mm^-1， F(000)=1256， R₁=0.0263， wR₂=0.0676 (I>2σ(I)). Compound 2 is dinuclear structure， in which each Cu(Ⅱ) adopts five-coordinated distorted square pyramid geometry. CCDC： 193109; 193110.