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1.
对氯苯基硫脲和2,4,6-三溴苯基硫脲的晶体结构和分子结构   总被引:1,自引:0,他引:1  
毛治华  单书香 《结构化学》1993,12(3):197-201
本文报道对氯苯基硫脲(Ⅰ)和2,4,6-三溴苯基硫脲(Ⅱ)的晶体结构和分子结构,(Ⅰ)属单斜晶系,空间群P2_1/a,a=10.671(1),b=8.912(1),c=9.128(1),β=106.85(1)°,Z=4,D_c=1.492g/cm~(-3),最后的偏离因子R=0.029,R_w=0.031;(Ⅱ)属正交晶系,空间群Pcab,a=9.997(2),b=7.876(4),c=27.920(3),Z=8,D_c=2.35g/cm~(-3),最后的偏离因子R=0.047,R_w=0.047。晶体结构测定结果表明,硫脲部分的四个原子组成平面三角形,苯环平面与硫脲平面的夹角分别为70.1°和80.3°。  相似文献   

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通过三(邻甲苯基)氢化锡与1-乙炔基环己醇和1-乙炔基环戊醇发生加成反应,得到两个加成物:(Z)-1-[2-(三-邻甲苯基锡基)乙烯基]环戊醇(1)和(Z)-1-[2-(三-邻甲苯基锡基)乙烯基]环己醇(2).通过元素分析、红外光谱和核磁共振氢谱等手段对其结构进行了表征.用X射线单晶衍射测定了加成物1和2的晶体结构.二者均为具有分子内O→Sn弱配位的扭曲四面体结构.1属于单斜晶系,P21/n空间群,晶胞参数:a=1.0496(2)nm,b=1.7658(4)nm,c=1.3193(3)nm,β=90.60(3)°,V=2.4451(8)nm3,Z=4,R=0.0317,wR=0.0820.2属于三斜晶系,空间群P1,晶胞参数:a=O.85592(17)nm,b=0.93016(19)nm,c=1.6368(3)nm;α=83.76(3)°,β=82.69(3)°,γ=78.05(3)°;V=12600(4)nm3,Z=2,R=0.0377,wR=O.1030.  相似文献   

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X射线衍射法测定了6-对硝基苯基-2-环己烯酸(1)和6-对甲氧苯基-2-环已烯酸(2)的晶体结构。晶体(1)属三斜晶系,空间群为P1,晶胞参数a=10.300,b=8.062,c=7.804A,α=71.39,β=80.40,γ=74.77°,Z=2,偏离因子R=0.073。晶体(2)属单斜晶系,空间群为P2_1/c,晶胞参数a=16.550,b=5.583,c=14.600A,β=116.0°Z=4,偏离因子R=0.048。根据实验结果对成环加成反应的活性和区域选择性进行了讨论。  相似文献   

4.
周为群  陆路德  杨绪杰  曹阳 《化学学报》2004,62(16):1472-1476
合成了未见报道的N-(2-氟苯甲酰基)-N′-4-甲基苯基硫脲(FBTT),并测定了其晶体结构.晶体属三斜晶系,空间群P1,a=0.8413(5)nm,b=0.9532(5)nm,c=0.9927(6)nm,α=66.24(2)°,β=85.40(2)°,γ=72.27(2)°,V=0.693.2(7)nm3,Z=2.利用量子化学密度泛函理论,以步长为30°旋转扭角θ[N(2)-C(14)-N(1)-H(12)]得势能曲线.优化的最稳定的构型与得到的晶体结构一致.讨论了分子的构型,估算了氢键的键能.  相似文献   

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本文合成了7,8,17,18-四溴-5,10,15,20-四苯基-21,23(H)-卟啉(H_2TPPBr_4)及其金属配合物MTPPBr_4[M=Cu(Ⅱ),Ni(Ⅱ),Co(Ⅱ)和Zn(Ⅱ)],测定了它们的可见紫外光谱和循环伏安,用四轨道模型(Four Orbital Model)计算了MTPPBr_4的相对前线轨道,并解释了配合物的可见紫外光谱及电化学性质.测定了NiTPPBr_4的晶体结构,晶体属单斜晶系,空间群为C2/c,a=2.6077(7),b=1.0414(4),c=1.9312(3)nm,β=137.1(7)°,Z=4,最后偏离因子R=0.067,晶体结构直接证明了卟啉亲电溴化反应具有区域选择性,四个溴分布在相对两个吡咯环上.  相似文献   

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刘胜利  戴静芳  陈勇  曹国标  刘汉文 《有机化学》2004,24(12):1583-1586
合成了3-(2-羟基苯基)-5-苯基-6-乙氧羰基-2-环己烯酮.通过元素分析、红外光谱、紫外光谱、核磁共振氢谱和质谱对其组成和结构进行了表征.利用X射线衍射分析方法测定了它的晶体结构.该化合物的晶体属单斜晶系,空间群P21/c,a=1.41946(17)nm,b=0.58445(7)nm,c=2.1756(3)nm,β=104.795(2)°,V=1.7450(4)nm3,Z=4,Dc=1.280 g·cm-3,F(000)=712,μ=0.088mm-1,R1[I>2σ(I)]=0.0627,wR2[I>2σ(I)]=0.1484.晶体结构测定结果表明化合物分子中的环己烯部分为半椅式构象,分子间通过氢键形成具有16元环的二聚体.  相似文献   

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合成了一种新的对硝基苯甲醛缩对羟基苯甲酰腙晶体;利用红外光谱、紫外光谱和元素分析对其进行了表征,并利用单晶X射线衍射测定了其晶体结构.结果表明,该晶体属于单斜晶系,P2(1)/n空间群;晶胞参数a=0.766 17(2)nm,b=1.357 3(3)nm,c=1.256 0(3)nm,β=92.71(3)°,V=1.304 7(4)nm3,Z=4,Dc=1.452 g/cm3,μ=0.109 mm-1.12 593个可观察独立衍射点(I2σ(I))偏离因子R1=0.042 5,wR2=0.142 4,S=1.096.  相似文献   

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N-二茂铁甲酰基-N'-对乙酰基苯基硫脲的晶体及分子结构   总被引:15,自引:0,他引:15  
合成的标题化合物晶体属单斜晶系, 空间群为P2~1/α, 晶胞参数为:α=0.9771(2), b=1.6752(6), c=1.1552(3)nm; β=109.23(2)°, 体积V=1.785(2)nm^3, Z=4, D~x=1.42g/cm^3, 最终偏差因子R=0.047, R~ω=0.051。结构分析表明, 在N'H-C(S)-NH-C(O)中的羰基氧和N'上的氢之间生成分子内氢键, 其为包括氢原子在内的平面六元环, 并且在二茂铁中的两个茂环平行。结合^1HNMR, IR谱矛以确证, 指出N原子上的氢应在高场(~8.0)N'上的氢原子化学位移应在低场(~12,0)。  相似文献   

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本文合成了7, 8, 17, 18-四溴-5, 10, 15, 20-四苯基-21, 23(H)-卟啉(H~2TPPBr~4)及其金属配合物MTPPBr~4[M=Cu(II), Ni(II), Co(II)和Zn(II)]。测定了它们的可见紫外光谱和循环伏安, 用四轨道模型(Four Orbital Model)计算了MTPPBr~4的相对前线轨道, 并解释了配合物的可见紫外光谱及电化学性质。测定了NiTPPBr~4的晶体结构, 晶体属单斜晶系, 空间群C2/c, a=2.6077(7),b=1.0414(4), c=1.9312(3)nm, β=137.1(7)°, Z=4, 最后偏离因子R=0.067, 晶体结构直接证明了卟啉亲电溴化反应具有区域选择性, 四个溴分布在相对两个吡咯环上。  相似文献   

10.
合成了LaⅢ和HoⅢ离子与对甲苯磺酰β-丙氨酸的配合物,并进行了元素分析、红外等表征,测定了两个配合物的晶体结构.配合物组成为[Ln2(Ts-β-AlaH)6 (H2O)4]n·4nH2O (Ln=La(1),Ho(2),Ts-β-AlaH=N-对甲苯磺酰β-丙氨酸),配合物均属单斜晶系,P21/n空间群,晶胞参数: 配合物(1) a=0.9563(2) nm,b=1.9113(3) nm,c=2.2933(4) nm,β=100.04(2)°,Z=4,Mr=937.77,Dc=1.509 kg·m-3,F(000)=1912,R1=0.0367,wR2=0.0944;配合物(2) a=0.9545(2) nm,b=1.8971(4) nm,c=2.2930(6) nm,β=100.19(2)°,Z=4,Mr=963.79,Dc=1.566 kg·m-3,F(000)=1952,R1=0.0363,wR2=0.0991.配合物(1)和(2)均为一维链状结构,但链中羧基桥连方式不同;同时两个金属离子一个是9配位,一个是8配位.  相似文献   

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We review our research on the synthesis and study of the physical and biological properties of furyl- and thienylgermatranes and -silatranes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 725–732, June, 1992.  相似文献   

14.
The use of the insect cell/baculovirus expression system for producing recombinant proteins of bacterial, plant, insect, and mammalian origin has become widespread. The popularity of this eukaryotic expression system is due to many factors, including (1) potentially high protein expression levels, (2) ease and speed of genetic engineering, (3) ability to accommodate large DNA inserts, (4) protein processing similar to higher eukaryotic cells (e.g., mammalian cells), and (5) ease of insect cell growth (e.g., suspension growth). The following review of the literature discusses two engineering aspects of recombinant protein synthesis by insect cell cultures: bioreactor scale-up and insect cell line selection. Following this review patent abstracts and additional literature pertaining to expression of recombinant proteins in insect cell culture are listed.  相似文献   

15.
多环芳二酐型聚酯亚胺膜的透气性能李悦生,丁孟贤,徐纪平(浙江大学高分子科学与工程研究所,杭州,310027)(中国科学院长春应用化学研究所)关键词聚醚酰亚胺,聚酯酰亚胺,膜,透气性通常的聚酰亚胺加工性能较差,在芳环二酐的苯环间引入醚键等柔性基团后,其...  相似文献   

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The aromaticity and antiaromaticity of the ground state (S 0), lowest triplet state (T 1), and first singlet excited state (S 1) of benzene, and the ground states (S 0), lowest triplet states (T 1), and the first and second singlet excited states (S 1 and S 2) of square and rectangular cyclobutadiene are assessed using various magnetic criteria including nucleus-independent chemical shifts (NICS), proton shieldings, and magnetic susceptibilities calculated using complete-active-space self-consistent field (CASSCF) wave functions constructed from gauge-including atomic orbitals (GIAOs). These magnetic criteria strongly suggest that, in contrast to the well-known aromaticity of the S 0 state of benzene, the T 1 and S 1 states of this molecule are antiaromatic. In square cyclobutadiene, which is shown to be considerably more antiaromatic than rectangular cyclobutadiene, the magnetic properties of the T 1 and S 1 states allow these to be classified as aromatic. According to the computed magnetic criteria, the T 1 state of rectangular cyclobutadiene is still aromatic, but the S 1 state is antiaromatic, just as the S 2 state of square cyclobutadiene; the S 2 state of rectangular cyclobutadiene is nonaromatic. The results demonstrate that the well-known "triplet aromaticity" of cyclic conjugated hydrocarbons represents a particular case of a broader concept of excited-state aromaticity and antiaromaticity. It is shown that while electronic excitation may lead to increased nuclear shieldings in certain low-lying electronic states, in general its main effect can be expected to be nuclear deshielding, which can be substantial for heavier nuclei.  相似文献   

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微量元素与疾病诊断治疗的研究现状及展望   总被引:8,自引:0,他引:8  
对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述,包括:微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。  相似文献   

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