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1.
本文对强效镇痛剂羟甲芬太尼(OMF)八个对映异构体中的其中四个, 即(-)-cis-(3R,4S,2'R)-OMF (1), (+)-cis-(3-R,4S,2'S)-OMF (2),(+)-trans-(3S,4S,2'R)-OMF (3), 和(+)-trans-(3S,4S,2'S)-OMF (4)进行了^1HNMR研究, 归属了所有的共振谱线。对哌啶环质子间偶合常数的分析表明, 所有顺式和反式异构体中的哌啶环都呈现相同的椅式构象。在顺式异构体中3-甲基位于直立键, 而4-N-苯基丙酰胺基位于平伏键, 反式异构体中它们均位于平伏键。讨论了3-甲基和4-N-苯基丙酰胺基的立体取代对NMR的影响, 在顺式异构体中4-N-苯基丙酰胺基的构象相对固定, 而在反式异构体中则较为自由。  相似文献   

2.
本文报道2-p-硝基苯基-4-甲基-2,3,4,5-四氢-(1,5)-苯并硫氮杂(艹卓)的两个顺反式异构体的晶体结构.顺式异构体属正交晶系,空间群为 D_(2h)~(10)—Pbnb,晶胞参数:a=8.326(1),b=14.865(5),c=24.533(4)(?);d_c=1.31g/cm~3;Z=8;F(000)=1264;μ_(MoKα)=2.2cm~(-1).反式异构体属单斜晶系,空间群为 C_(2h)~6-C2/c,晶胞参数:a=22.366(3),b=12.488(2),c=12.483(2)(?);β=121.01(1)°;d_o=1.34g/cm~3;Z=8;F(000)=1264;μ(MoKα)=2.2cm~(-1).晶体结构由 SHELXTL 直接法程序解出,用块矩阵最小二乘法修正,最后的偏离因子:顺式异构体 R=0.0661,R_w=0.0661;反式异构体,R=0.0705,R_w=0.0571.结构分析表明:顺式异构体为类椅式构象,反式异构体为类扭船式构象.这为进一步归纳这类化合物的结构特征和立体化学规律提供了条件.  相似文献   

3.
标题化合物由[(μ-CO)(μ-C_2H_5S)Fe_2(CO)_6](C_2H_5)_3NH和反式或反式-C_6H_5CH=CHBr制得。其晶体属空间群C_c;a=1.8053 nm,b=1.0436 nm,c=1.9045 nm;β=93.68°;D_c=1.66g/cm~3;Z=8;R=0.0413。Fe—Fe键长为0.2542nm,苯乙烯基配体的C=C双键为0.1358 nm,乙基以e-键与硫桥原子相连。  相似文献   

4.
本文报道2-p-硝基-4-甲基-2,3,4,5-四氢-(1,5)-苯并硫氮杂 的两顺反式异构体的晶体结构. 顺式异构体属正交晶系, 空间群为反式异构体属单斜晶系, 空阒空间群为 , 晶胞参数:晶体结构由SHELXTL直接法程序解出, 用块矩最小二乘法修正, 最后的偏离因子:顺式异构体结构分析表明: 顺式异构体为类椅式构象, 反式异构体类扭船式构象. 这为进一步归纳这类化合物的结构特征和立体化学规律提了条件.  相似文献   

5.
四氢-2-甲基-4-芳基-1,5-苯骈硫氮杂(艹卓)的结构式为:X可为:H、o-OCH_3、p-OCH_3、o-Br、o-NO_2、m-NO_2、p-NO_2、o-Cl、m-Cl、和p-Cl我们曾报告了有关该类化合物的制备和立体化学。 合成产物(Ⅰ)是顺式和反式两种异构体的混合物。根据构象分析和NMR谱分析,其中反式异构体具有扭船式构象,具有较高的熔点(Ⅱ);顺式异构体具有椅式构象,熔点较  相似文献   

6.
本文通过氨基甲酰基膦酰胺酯与4-(取代)苯基二氯化膦缩含,然后硫化的方法制备了一类新型的双磷杂环化合物——4,5-二氧-2-硫-1,3,2,4-二氮二磷杂环戊烷。利用HPLC分离出了顺式和反式异构体,并分别测定了其晶体结构。通过~1HNMR和~(31)P NMR谱研究了化合物的立体结构,顺式和反式异构体有不同的化学位移和偶合常数。生物测定初步结果表明,这些化合物都有一定的除草活性,其中个别化合物有较高的除草活性。  相似文献   

7.
施剑秋  程培元 《结构化学》1992,11(6):471-475
冬凌草甲素,C_(20)H_(28)O_6,Mr=364.44,是一种从中药中提取的抗癌药,它的晶体结构分析表明晶体属正交晶系的空间群P2_12_12_1,晶胞参数为α=13.316(9),b=21.302(2),c=13.015(1),V=3697(9)~3。Z=8,D_c=1.31g/cm~3,D_o=1.30g/cm~3,F(000)=1568。该分子是四环二萜类化合物,A环和C环是椅型结构,B环是船型结构;D环是部分共轭五员环,为半椅型结构,环上相邻的两个双重键侧基组成一个六原子的共轭平面。  相似文献   

8.
合成的标题化合物用X射线衍射方法确定其分子的绝对构型,晶体空间群为P_(2_1 2_1 2_1),晶胞参数:a=0.8365(3)、b=0.8625(3)、c=2.3513(2)nm,Z=4.结构分析表明,分子骨架中存在3个环结构,即含磷、氮原子的船式七元环、椅式六元环以及由碳原子组成的信封式五元环。P—S键为e键,P—O键为a键。  相似文献   

9.
对由二乙烯三胺与联苯甲酰合成的标题化合物进行了MS、IR、UV、NMR谱的表征及X射线单晶衍射结构分析.该化合物M_r=277.39,晶体属P2_1/n空间群,晶胞参数a=0.9442(2)nm,b=1.4344(4)nm,c=1.1824(3)nm.β=112.92(2)°,Z=4,D_c=1.25g·cm~(-3).晶体结构由直接法解出,1827个可观察衍射参与最小二乘法修正,最终偏差因子R=0.050.结果表明标题化合物是一非平面型,具有部分不饱和键的氮杂稠二环化合物,其母体六元环为椅式构型、五元环为半椅式构型,2个取代苯基间的夹角为73.5°.  相似文献   

10.
标题化合物PhS(CH_2)_2SPhPtCl_2,由Pt(Ⅳ)通过不稳定中间产物直接合成。配合物晶体属单斜晶系,空间群C_(2h)~5-P2_1/c。晶胞参数:a=9.735(1),b=10.056(1),c=14.718(2),β=101.07(1)°,V=1554.6,D_c=2.19g/cm~3,Z=4。分子为单核顺式四配位螯合结构,用姜-台勒效应讨论了分子构型的畸变。  相似文献   

11.
报道了标题化合物〔C14H18Br2OSn〕的合成及晶体结构。该晶体属于单斜晶系,空间点群为P21/c,晶胞参数a=11.711(2),b=9.114(2),c=16.864(3)A,β=102.94(1)°,V=1604.55(0)A3,Mr=480.78,Z=4,Dc=1.99g/cm3,u=65.20cm-1,F(000)=919,R=0.050,Rw=0.050.晶体结构由直接法解出。标题化合物分子中的锡原子被配体的2个碳、2个溴和1个氧原子配位,配位原子呈畸变的三角双锥构型,环已基为椅式构象,五员杂环为信封构象。  相似文献   

12.
<正> The title complex [Ni(TTA)2(DMSO)] (TTA = thenoyl trifluo-roacetone, DMSO=dimethyl sufloxide) belongs to triclinic, space group P1, parameters of crystal cell: a = 9.447(l), b = 10.505(1), c=11. 912(1)(?) , α=97. 42(1), β= 84. 00(1), γ = 102. 08(1)°, V = 1143. 3(?)3, Z = 2, Mr = 581. 22 [Ni (C8H4O2F3S)2(CH3)2SO)], Dc=1. 688g. cm-3, F(000) = 588, final R = 0. 065 and Rw = 0. 072 for 2873 reflections with I≥3σ(I). In the title complex the nickel atom has a square pyramidal geometry with four short Ni-O bonds and one long Ni -O (DMSO) bond.  相似文献   

13.
<正> Complexes [(η8-C8H8)LnCl(OC4H8)2]2, (Ln = Pr(1), Nd(2)) both crystallize in monoclinic space group P21/n with cell dimensions for 1: a = 11. 860(3), b=12. 697(3), c=12. 161(2)(?), β=111. 88(2)°, V= 1699. 50(69) (?)3, Dc=1. 66gcm-3,Z==2 (4 monomers), μc=30. 2cm-1, F (000) = 848, the final R = 0. 031, Rw = 0. 032 for 2303 independent reflections with I≥ 3σ(I) ; and for 2: a=11. 834(4), b = 12. 666(5), c=12. 166(3)(?), β=111. 73(2)°, V= 1694. 03 (99)(?)3, Dc= 1. 68g. cm-3, Z = 2 (4 monomers), μc=32. 3cm-1, F(000) = 852, R=Rw = 0. 035 for 3487 independent reflections with I≥3σ(I). In each complex, there are two Ln atoms in a dimeric unit which are bridged asymmetrically by two chloride ions with Ln - Cl bond lengths of 2. 847(2) and 2. 924(2)(?) for 1, or 2. 836(1) and 2. 919(2)(?) for 2. The cyclooctatetraene COT dianion ring is planar with eightfold molecular symmetry and an average C -C bond length of 1. 392(?). It is symmetrically coordinated to the Ln atom with an average Ln - C distance of  相似文献   

14.
<正> Compound C9H19N2OPS (1) , Mr = 234. 3, monoclinic, space group P21, a = 7. 5637(2), b = 7. 704(2), c=10. 258(1) (?) ,β = 98. 66(2)°, V = 590. 9(?)3, Z =2, Dc=1. 317g/cm3, F(000) = 252. The final R = 0. 063 and Rw = 0. 080 with unit weight for 870 observed reflections (I≥3σ(I)). Compound C10H22 N3PS(2), Mr = 247. 34, monoclinic, space group P21, a = 7. 656(1), b = 8. 248 (1), c=10.750(l)(?), β=91.31(1)°, 7 = 678.73(?)3, Z = 2, Dc=1. 21g/cm3, final R = 0. 066 and Rw = 0. 081 with unit weight for 813 observed reflections (I≥3σ (I)), F(000) = 268. Both skeletons of (1) and (2) have similar geometry, which is composed of three rings : a seven-membered ring in a boat form, a six-membered ring in a chair conformation, and a five-membered ring in envelope form. The configura-tions of the chiral phosphorus atoms are assigned as 3R for (1) and as 3S for (2).  相似文献   

15.
1INTRODUCTIONChiralphosphinesareusefulligandsinenantioselectivecatalysiswithtransitionmetalcomplexes"',someofthemderivedfromsugarsarealsoofPOtentialapplicationsinbiphasiccatalysis"'andmedicinet3i.Bythenucleophilicreplacementreaction,itisdifficulttolinkthephosphorusatomtothesecondarycarbonofpyrano--,orfurano--sugarderivativesbecauseofthecompetingeliminationreaction[4i.Wehavefoundaneffectivemethodtoincorporateaphosphorusintoapyranosering"',viaregioselectiveandstereospecificring--openingreac…  相似文献   

16.
<正> The title cluster Fe3(CO)8[CNH C(CH)4CNH] (μ3-S)2 has beensynthesized and its crystal and molecular structure determined. Crystal data: C15 H6N2O8S2Fe3, Mr = 646. 27, triclinic, space group P1, a = 8. 6664(1), 6=10. 7857 (2), c=12.5536(3)(?),α=112. 3944(2), β=106. 4103(2) ,γ = 95.541(1)°, V = 1012. 8(?)3. Z = 2, Dc=1. 888gcm-3, μ=23. 639cm-1, final R = 0. 0477, Rw =0. 0535 for 2583 independent reflections. The cluster is a carbene derivative of Fe3-(CO)9S2, and contains a heterocyclic fragment c as the carbene ligand whichreplaces a terminal axial CO ligand of atom Fe(l) and locates in a vertical position to the distorted basal plane formed by Fe(1)S(1)Fe(2)S(2). The geometry of Fe3-(CO)9(μ3-S)2 has been maintained in the title compound but some of the Fe-S bond lengths have been changed.  相似文献   

17.
<正> Kopsamine(I): Mr=456.50, orthorhombic, P212121, a=ll.245(3), b=12.547(2), c=15.043(3)A, Z=4, Dc=1.429g.cm-3, V=2122.5A3, final R=0.041 for 2008 observed reflections.N-carbomethoxy-11-methoxy-12-hydroxy-kopsinaline(Ⅱ): Mr=458.52, mono-clinic, P21,a=8.424(2), b=13.037(1), c=9.883(1)A,β=90.14(2)°, Z=2, Dc= 1.403g·cm-3, V=1085.4 A3, final R=0.039 for 1687 observed reflections.In the structures: The rings A,B and E(I) take envelop conformations. The ring C takes chair conformation and the ring D boat conformation. There are intramolecular hydrogen bonds 0(5)-HO(5)...0(1) both in molecule(I) and molecule(Ⅱ), which formed the distorted seven-membered ring with atoms C(22), N(1), C(2), and C(18).  相似文献   

18.
金玑洙  金钟声 《结构化学》1992,11(3):204-207
本文报导了(Cp_2ErCl(THF)]_2的晶体结构,晶体属单斜晶系,P2_1/c空间群。晶胞参数为a=8.141(2),b=21.218(6),c=8.597(2),β=107.77(2)°;V=1414.1(6) ~3;Z=2,D_c=1.90g/cm~3,F(000)=780,μ_c=66.3cm~(-1)(MoK_a)。最终的偏离因子R=0.047,R_(to)=0.048。结构分析表明,该配合物是以两个氯离子与金属离子桥联的二聚体形式存在。四氢呋喃中的氧原子同金属离子键合,Er—O键长为2.490(6),两个环戊二烯中的所有碳原子同金属离子间的平均键长为2.649,Er-Cl=2.666(3),Er—Cl-a=2.797(3),Er-Er_a=4.42,Cl-Er-Cl_a键角为72.2°。  相似文献   

19.
谌了容  喻宗沅 《结构化学》1992,11(2):118-121
<正> C18H18O6·H2O, Mr = 348. 34, cis-isomer: orthorhombic, Cmc21, a = 16. 421(3), 6 = 11.978(1), c=8. 624(1)(?), V = 1696. 2(?)3, Z = 4, Dc= 1.293 gcm-3, λ(MoKα) = 0. 71073(?), μ = 0. 911cm-1, F (000) = 763, R = 0. 043, Rw = 0. 042 for 769 unique observed reflections. trans-Isomer : orthorhombic, Cmc21, a = 16. 503(2), b = 12. 297(2), c=8. 557(3) (?). V = 1736(?)3, Z = 4, Dc= 1.271 gem-3, λ(MoKα) = 0. 71073(?), μ = 0. 892cm-1, F (000) = 736, R=0.048, Rw = 0. 046 for 551 unique observed reflections. The configurations of the two molecules appear as butterflies. There is a Cm symmetry in the molecule of each isomer.  相似文献   

20.
<正> The reaction of [Et4N][Mo(CO)4(S2CNEt2)] with tetraethylam-monium tetrathiomolybdate affords a new mixed-valence dinuclear molybdenum complex [Et4N]2[(CO)4MoS2MoS2] (1). 1 crystallizes in the orthorhombic space group Pbom with a = 18.403(2), b = 11.963(1), c= 13. 482(1)(?) , Z = 4, V = 2986(?)3, Dc=1. 55g/cm3, Mr = 6S2. 69. R =0. 042 and Rw =0. 057 for 1975 independent reflections with I≥3σ(I), F(000) = 1416, μ =11. 2cm-1. The structure of the anion of 1 consists of an octahedron for the lowvalent Mo atom and a tetrahedron for the high-valent Mo atom sharing an S - S edge. The Mo - Mo bond distance is 2. 992 (2) (?) and the bimetallic center MoS2Mo is planar with Mo-S of 2. 517 and 2. 231 A and MoSMo angles of 78. 04° and 77. 67°. The electron delocalization between the two Mo atoms with wide separated oxidation states is also discussed.  相似文献   

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