希土取代苯基化合物的合成

1970年Hart等利用苯基锂的乙醚溶液与希土氯化物的四氢呋喃悬浮液反应,首次合成了希土苯基化合物(C_6H_5)_3Ln(Ln=Sc、Y),LiLn(C_6H_5)_4(Ln=La、Pr),但没有得到满意的碳氢分析数据,碳的实测值仅为计算值的三分之二左右。其他希土苯基化合物的合成也有报道。为了进一步探索希土芳基化合物的合成方法,希土和芳基之间成键的可能性,我们使用邻甲氧基苯基锂和对甲基苯基锂与希土氯化物反应,试图合成新的希土取代苯基化合物。     

X-ray crystallographic structure and physical properties of the pentacoordinated [TPAFeCl] complex

A new pentacoordinated ferrous compound [TPAFeCl]⁺ (TPA = tris(2-pyridylmethyl)amine) was synthesized from the reaction between H₃TPA(ClO₄)₃ and Fe(PⁿPr₃)₂Cl₂ in MeCN. The unique trigonal bipyramidal [TPAFeCl]⁺ complex was characterized as a S = 2 high spin complex based on the crystallographic structure, magnetic susceptibility, ¹H NMR spectrum and semi-empirical ZINDO/S calculations. Crystal of [TPAFeCl]₂(FeCl₄)(MeCN)₂ was monoclinic with a = 12.019(2) Å, b = 27.550(5) Å, c = 14.138(2) Å, β = 94.168(3)°, V = 4668.9(13) Å³, space group C/c, and the unit cell contained a racemic mixture of Δ and Λ isomers with ferrous tetrachloride anion.     

NAK-12树脂脱除蚕蛹复合氨基酸异味及褐变物质的研究

本文研究了用NAK－12吸附树脂脱除蚕蛹复合氨基酸异味及褐变色素的条件，初步分析了蚕蛹复合氨基酸异味产生的原因，实验结果表明：当流速为3BV／h时，1ml NAK-12吸附树脂能吸附1．75g蚕蛹复合氨基酸中的异味物质；能吸附1．45g蚕蛹复合氨基酸中的褐变物质。甲醇是异味物质和褐变物质的良好洗脱剂，用pH1．0的甲醇以1BV／h流速洗脱，仅用3．5BV的洗脱剂即可完全洗脱异味物质和褐变物质，蚕蛹复合氨基酸异味产生的可能机理是：加热蚕蛹复合氨基酸液时，其苯丙氨酸，蛋氨酸，蛋氨酸，异亮氨酸，亮氨酸，苏氨酸被氧化脱氨，生成挥发性醛，而其褐变则是赖氨酸，精氨酸与还原糖发生Maillard反应生成褐变物质引起的。     

双马来酰亚胺增韧研究Ⅱ.链扩展双马来酰亚胺及其树脂的合成及表征

合成了一系列结构不同和链长短不一的双马来酰亚胺，并对其结构和性能作了表征，同时研究了它们的固化反应和固化产物的性能。用双马来酰亚胺和二烯丙基化合物反应制造了增韧树脂，研究了该树脂的固化和热稳定性。     

One Novel Vanadium-Phosphate Cluster [PV_(2.5)O_(8.5)]-3.83{H_2O} with Three-Dimensional Architecture

A novel vanadium-phosphate compound [PV_2.5O_8.5]·3.83{H_2O}(1)was obtained from the hydrothermal reac-tion and structurally characterized by elemental analysis and single-crystal X-ray diffraction,which exhibited thatthe title complex crystallized in cubic space group I-43m with crystal data:a=1.6115(1)nm,V=4.1848(1)nm~3,Z=12,D_c=1.783 g/cm~3,F(000)=2278,R_1=0.0528,and wR_2=0.1329[I>2σ(I)](all data).The basic unit of{PV_2.5O_8.5}symmetrically extended to closed sphere-like structure of{P_4V_(10)O_(34)},which was further linked to in-terleaving three-dimensional network via sharing four phosphate through μ_3-oxygen atoms around the closedsphere-like structures.     

Sequosempervirin A, a novel spirocyclic compound from Sequoia sempervirens

A novel spirocyclic compound (4R)-4-(4-hydroxy-benzyl) spiro [4,5] dec-1-en-8-ol (sequosempervirin A) was isolated from the branches and leaves of Sequoia sempervirens. Its structure and relative stereochemistry were mainly determined by MS, 2D NMR and X-ray means, which is the first naturally occurring norlignan containing one spirocycle with C6 (cyclohexane)-C2-C3-C6 skeleton.     

A novel boron-rich quaternary scandium borocarbosilicide Sc3.67−xB41.4−y−zC0.67+zSi0.33−w

A novel quaternary scandium borocarbosilicide Sc_3.67−xB_41.4−y−zC_0.67+zSi_0.33−w was found. Single crystallites were obtained as an intergrowth phase in the float-zoned single crystal of Sc_0.83−xB_10.0−yC_0.17+ySi_0.083−z that has a face-centered cubic crystal structure. Single crystal structure analysis revealed that the compound has a hexagonal structure with lattice constants a = b = 1.43055(8) nm and c = 2.37477(13) nm and space group (No. 187). The crystal composition calculated from the structure analysis for the crystal with x = 0.52, y = 1.42, z = 1.17, and w = 0.02 was ScB_12.3C_0.58Si_0.10 and that agreed rather well with the composition of ScB_11.5C_0.61Si_0.04 measured by EPMA. In the crystal structure that is a new structure type of boron-rich borides, there are 79 structurally independent atomic sites, 69 boron and/or carbon sites, two silicon sites and eight scandium sites. Boron and carbon form seven structurally independent B₁₂ icosahedra, one B₉ polyhedron, one B₁₀ polyhedron, one irregularly shaped B₁₆ polyhedron in which only 10.7 boron atoms are available because of partial occupancies and 10 bridging sites. All polyhedron units and bridging site atoms interconnect each other forming a three-dimensional boron framework structure. Sc atoms reside in the open spaces in the boron framework structure.     

金属有机导体、半导体和超导体

本文综述了三类金属有机固体化合物的合成、结构与导电性能。这三类化合物是金属有机电荷转移盐,金属酞菁和会属卟啉络合物,以及金属有机夹层化合物。     

含苯并呋喃、苯并噻吩环的聚苯基-1,2,4-三嗪

本文首次合成了几种含苯并呋喃苯并噻吩环的新的芳香族四羰基化合物,并对它们进行了元素分析和红外光谱测定。将所合成的芳族四羰基化合物分别与芳族双酰胺腙反应,得到了一系列含氧、硫杂原子的新的聚苯基-1,2,4-三嗪。这些高聚物均可以浇铸成膜。对聚合物所进行的一般性能测试的结果表明,它们具有良好的力学性能和较好的耐温性。     

含硒杂环化合物的合成和对超氧阴离子作用的ESR研究

引言硒作为人体必需的微量元素,其主要生化作用与谷胱甘肽过氧化物酶密切相关.在体内,该酶可以催化许多过氧化物的分解,并且与谷胱甘肽一起组成一个强有力的细胞防御体系,发挥其抗氧化作用.近几年来,人们发现了一种小分子有机硒化物2-苯基-1,2-苯并异硒唑酮-3(简称Ebselen)具有类似谷胱甘肽过氧化物酶的活性.它能有效地抑制活性氧自由基的产生而引起的细胞损伤,具有良好的抗炎活性,且毒性极低(大鼠LD_(50)>6180mg/os).因而,普遍认为Ebselen及其类似物是一类具有广谱抗炎活性的潜在药物,在医药领域具有广阔的应用前景.