双端氧配位原子簇化合物——[Fe(MoS_4O)_2][N(C_2H_5)_4]_3的晶体结构和分子结构

本文报道了含双端氧配位的Mo—Fe—S原子簇化合物[Fe(MoS_4O)_2][N(C_2H_5)_4]_3的合成、晶体结构和分子结构。该化合物的晶体属单斜晶系,P2_1/n空间群,晶胞参数为:a=13.019(4),b=16.959(5),c=18.234(5),β=97.34(2)(°),z=4。最终一致性因子为:R=0.0740,R_w=0.0598。该化合物中的Mo—S_t端键和Mo—S_b桥键比不合端氧配位的相应化合物Mo—S键长长得多,可能是由于Mo的价态降低和氧的电负性比硫大得多,氧对Mo的配位使s→→O发生电荷转移的缘故。     

异构N-苯基-5-降冰片烯-2,3-二羰基酰亚胺(C_(15)H_(13)NO_2)的晶体和分子结构研究

异构N-苯基-5-降冰片烯-2,3-二羰基酰亚胺(C_(15)H_(13)NO_2)晶体属正交晶系,空间群P_(bca),Z=8,晶胞参数a=12.063(6),b=16.361(6),c=24.178(8)(?),V=4831(?)~3,D_c=1.32Mgm~(-3),每个独立区内有两个异构分子,μ(M_OK_α)=0.5c厘米~(-1)。在R_3系列四园衍射仪上用M_OK_α辐射,收集了可视察反射点(Ⅰ≥2.5σ(Ⅰ))4387个,结构用直接法解出。最后的一致性因子R=0.059(R_w=0.046)。本文给出了该化合物的分子和晶体构型,並描述了其结构特点。     

(η~5-C_5H_5)_3Nd·OC_4H_8和(η~5-C_5H_5)_3Pr·OC_4H_8的合成及其晶体结构

本文用LnCl_3(Ln=La,Pr,Nd)同环戊二烯钠在THF溶液中反应,制备出(η~5-C_5H_5)_3Ln·OC_4H_8化合物单晶.采用低温技术,在—60℃的干燥氮气保护下,收集(η~5-C_5H_5)_3HPr·OC_4H_8[(η~5-C_5H_5)Nd·OC_4H_8]的单晶X射线衍射数据,解出了晶体结构.它们同属单斜晶系,P2_1/n 空间群.结构表明,THF分子中的氧原子与金属离子键合,Pr—O键长为2.56(1)A,Nd—O键长为2.54(1)A.三个环戊二烯分子中的所有碳原子与金属离子的间距,均在成键范围,其平均键距Pr—C为2.80(2)A,Nd—C为2.78(2)A.它们同已报道的(η~5-C_5H_5Ln·OC_4H_8(Ln=Y,La,Gd)结构一起,可很好地解释镧系收缩理论,同时为研究稀土元素的价态和键,提供了有用的结构信息。     

CRYSTAL STRUCTURE OF N'- (2-TETRAHYDROF URANYL)- 5-FLUOROURACIL

N'-(2tetrahydrofuranyl)-5-fluorourancil, C_8H_9FN_2O_3,, crystals are triclinic system, a=6.004(2),b=9.022(8),c=16.702(11),α = 99.78(6),β=93.48(3),γ=94.18(6)°. Space group P,Z=4. The diffraction data (Mo K radiation) were collected with Nicolet R3 four-circle diffractometer. The structure was determined by SHELXTL direct methods and refined by least-squares program, R=0.078, Rw=0.069.The structure determination results show that the phase angles of pseudorotation in tetrahydrofuran ring are P=218.6°(mol. 1) and P=177.9°(mol. 2) respectively. Both molecules 1 and 2 arc of the type S[C(6)endo-C(7) exo]. The orientation of the uracil with respect to five-membered ring is positive, x=-53.1 (mol. 1) and x=-18.4(mol. 2).     

呋喃氟脲嘧啶的晶体结构

呋喃氟脲嘧啶C_8H_9FN_2O_3晶体属三斜晶系,a=6.0044(23),b=9.0221(80),c=16.7021(109),α=99.779(59),β=93.426(43),γ=94.178(55)°。空间群P_1~-,Z=4。用Nicolet R3四圆衍射仪收集强度数据,结构由SHELXTL系统的直接法解出。经最小二乘修正,R=0.078,R_w=0.069。结构测定结果表明,四氢呋喃环具有假旋转角P=218.6°(分子1)和P=177.9°(分子2),两个分子均为S型构造[C(6)endo—C(7)exo]。脲嘧啶基相对于五元环具有正的取向,x=—53.1(分子1)和x=—18.4(分子2)     

[(C_(16)H_(32)N_4)~(-4)·2Mn~(2+)·4HCl·[(C_(16)H_(36)N_4)·2H_2O]多元包合物的晶体结构

[(4氮间杂六甲基十四烷环)~(-4)·2Mn~(2+)]·4HCl·[4氮间杂六甲基十四烷环)·2H_2O]的晶体结构已用单晶X线衍射技术测定完成。它属于三斜晶系,P_1空间群,晶胞参数a=9.028(2),b=11.055(2),c=12.202(4),α=71.70(2),B=88.41(2),γ=75.32(2)~°,Z=1。对于2597个可观察独立反射计算R=0.073。结构分析证实,该晶体存在有四类物种,由负4价的四氮间杂六甲基十四烷环(简称电负性大环Ⅱ),2个Mn~(2+)正离子,4个HCl分子和一个携带2个结晶水的4氮间杂六甲基十四烷环(简称电中性大环Ⅰ)组成。 4个HCl分子处于电负性大环Ⅱ的周围,大环Ⅱ和Mn~(2+)离子间按离子键特点取空间最稳定构型与电中性大环Ⅰ沿c方向周期性交替排布,构成四元包合物O~-、N~-、Cl~-等电负性强的离子之间形成很强的H键网。 六十年代以来,以四氨间杂六甲基十四烷环作配体,以Co~(2+)、Co~(3+)、Ni~(2+)等金属离子为络合中心的大环络合物,国外已有许多报导。这些结构的共同特点是大环配体的4个氮原子围绕金属离子以构成四配位或六配位结构,研究表明,络合以后金属的电子组态发生了变化。 近来,我们将Mn~(2+)与上述的配体反应,结果得到与上述结构绝然不同的化合物。NMR谱证实,该化合物中包含电中性和电负性两种大环。环伏安法测其锰离子是2价正离子(详见     

A CLUSTER COMPOUND WITH DI-ENDOXYGEN LIGANDS——THE CRYSTAL AND MOLECULAR STRUCTURE OF [Fe(MOS_4O)_2][N(C_2H_5)_4]3

[Fe(MoS_4O)_2] [N(C_2H_3)_4]_3 cluster compound with di-end-oxygen ligands has been prepared and characterized by the X-ray diffraction method. The compound crystallizes in a monoclinic space group P2_1/n with lattice parameters a=13.019(4), b=16.959(5), c=18.234(5), β=97.34(2)(°), Z=4. The final agreement factors are R=0.0740, Rw=0.0598. The terminal bond length, Mo-S_t and bridged one, MO-S_b for the compound are much longer than the counterpart without end-oxygen ligand. It possibly suggests that low valence of molybdenum and smaller electronegativity of sulphur than oxygen lead to the charge transfer as S→Mo→O.     

INVESTIGATION ON SYNTHESIS, STRUCTURE AND PROPERTIES OF THE CLUSTER COMPLEX,[(MoS_4)Fe(MoS_4O)] [(C_4H_9)_4N]_3

In this paper, we report a new Mo-Fe-S cluster complex containing an oxygen ligand. Itwas synthesized by the reaction of (NH_4)_2 MoS_4, FeCl_3 in the solution of sodium glycol. The chemical formula of the crystal, [(MoS_4) Fe (MoS_4O)] [(C_4H_9)_4N]_3, was characterized byX-ray. This complex was determined by IR, UV/Vis and Mossbauer spectra as well. The re-suits from Mossbauer spectra of the complex show an isomer shift, δ_m = 0.2263mm/s and aquadrupole splitting, E_q = 0.4527mm/s. The complex has some activity for the reduetion of aectylene to ethylene in the presenceof KBH_4.     

THE FORMATION AND CRYSTAL STRUCTURE OF (η~5-C_5H_5)_3Nd·OC_4H_8 AND (η~5-C_5H_5)_3Pr·OC_4H_8

Under suitable reactant ratios without sublimation or reerystallization, single crystals of(η~5-C_5,H_5)_3 Ln-OC_4H_8(In = La, Pr, Nd) could be prepared by the reaction of cyclopentadienylsodium with respective lanthanide trichlorides in THF. Using low temperature technique wehave collected the X-ray data of single crystals of the title compounds at -60℃ under N_2and determined crystal structures. (η~5-C_5H_5)_3 Pr·OC_4H_8, [(η_5-C_5H_5)_3 Nd·OC_4H_8] recrystallizesin the monoclinic space group P2_1/n[P2_1/n] with unit cell parameters a = 8.406(3) [8.364(3)],b = 24. 510(9) [24.467(9)], c = 8. 284(3) [8.254(3)] A, β= 101.60(3) [101.42 (3)], D_c = 1. 62 [1.65]gem~(-3) for z = 4 [4]. Least-square refinement has led to a final R value of 0.056 [0.063],R_W = 0.049 [0.062]. The THF molecule is coordinated to the Pr [Nd] atom at a Pr-O [Nd-O]bond length of 2.16(1) [2.54(1)], A. The Pr-C (Cp) [Nd-C(Cp)] bond distances average 2.80(2) [2.78(2)] A. The title compounds are isostructaral with (η~5-C_5H_5)_3     

{Mo[S_2CN(C_2H_5)_2]_4}~( 1)·{FeCl_4}~(-1)·{C_6H_5CH_2S_2CH_2C_6H_5}三元包合物的晶体结构

成分为MoFeS_(10)Cl_4N_4C_(34)H_(54)的单晶样品,用SYNTEX-R3型四圆衍射仪以θ/2θ扫描方式收集3499个独立的X射线衍射强度数据进行结构分析。晶体属空间群C_s~4—C_c,晶胞参数a=17.900(5),b=18.466(7),c=15.483(4),β=92.78(2)°,Z=4,经PL,K,B及吸收因子的校正得绝对强度,由Patterson函数先导出Mo参数,随后用Fourier法有层次地导出S,Fe,Cl,N,C等非氢原子的坐标参数,另由直接法亦导出大部分非氢原子的位置,所得结果是平行的。用块矩阵最小二乘法对坐标及各向同性与各向异性的热参数进行多轮的修正,最后加入全部氢原子,同时进行氢原子各向同性热参数的修正,得一致性因子R=0.054,结构分析证实:晶体中存在有三类物种,四个二乙胺基硫代甲酸根与Mo(Ⅴ)组成了{Mo[S_2CN(C_2H_5)_2]_4}~(=1)络离子,它与负络离子{FeCl_4}~(-1)交替排列构成了沿c轴方向伸展的空腔,而电中性的苄基二硫化物,则充填其间组成了结构新颖的三元体系包合物。