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1.
自从氮化硼陶瓷纤维用聚合物先驱体法[1]合成以后,硼氮六元环化合物越来越为人们所重视[2],文中在制备氮化硼纤维先驱体的过程中,合成了其中间产物,通过热缩合成环反应,合成了含有硼氮六员环的化合物,并采用色-质联用技术对其进行了表征。1 实验部分参照文献[3],改用液氮和丙酮为冷冻剂,控制温度在-50到-40℃,搅拌下向三氯化硼的正戊烷溶液中缓慢滴加三乙胺的正戊烷溶液,滴完后N2气氛下-50℃加丙酮冷凝回流2h,慢慢由-50℃升至室温,抽滤即得到白色产物Et3NBCl3(A)。将A溶于适量苯中[4,5],加入等物质的量的三乙胺,加热回流搅拌…  相似文献   

2.
The insertion of N,N′-dicyclohexylcarbodiimide at one of the Y-N bonds of the [(Me3Si)2N]3Y complex in toluene at 70 °C afforded the monoguanidinate diamide derivative { (Me3Si)2NC(N-cyclo-Hex)2}Y[N(SiMe)3]2 (1) (cyclo-Hex is cyclohexyl) in 72% yield. The reaction of equimolar amounts of sodium N,N′-dicyclohexyl-N″-bis(trimethylsilyl)guanidinate, which was prepared in situ from {(Me3Si)2N}Na and N,N′-dicyclohexylcarbodiimide, and YbI2(THF)2 in THF gave the [{(Me3Si)2NC(N-cyclo-Hex)2}YbI(THF)2]2 complex (2). An attempt to use this procedure for the synthesis of the yttrium compound { (Me3Si)2NC(NSiMe3)2}2YCl containing the sterically more hindered guanidinate ligand unexpectedly led to the formation of the diamide chloride complex [{(Me3Si)2N}2Y(THF)(µ-Cl)]2 (3). The structures of complexes 1–3 were established by X-ray diffraction. Compound 1 is mononuclear. Complexes 2 and 3 are dinuclear and contain two µ2-bridging halide ligands.  相似文献   

3.
The reaction of Sn[CH(SiMe3)2]2 and ethyne at ambient temperature affords a mixture of products, from which the title compound has been separated and identified by IR, 1H, and 13C NMR spectroscopy.  相似文献   

4.
Cp* 2Lu(-Cl)2 (1) was isolated following the reaction of Cp*Na (Cp* = 1, 3-(Me3Si)2C5H3) with LuCl3 in THF and subsequent treatment with toluene at 80°C. An X-ray structural investigation of1 was performed (MoK radiation, 2933 reflections,R = 0.020). The crystals are triclinic,a = 10.744(3) Å,b=11.821(2) Å, c=12.966(3) Å, a=71.54(1)°, =85.32(2)°, =74.83(1)°,Z = 2, space groupP-1. Two Lu atoms withdistorted tetrahedral coordination are linked by two chloride bridges with a mean Lu-Cl distance equal to 2.62 Å.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 568–570, March, 1993.  相似文献   

5.
The reaction of anhydrous SmCl3 with two equivalents of lithium N,N′-diisopropyl-N″-bis(trimethylsilyl)guanidinate in THF afforded the [{(Me3Si)2NC(NPri)2}2SmCl]2 complex (1) in 82% yield. Analogous reactions with YCl3 and GdCl3 produced the ate-complexes { (Me3Si)2NC(NPri)2}2Ln(µ-Cl)2Li(THF)2 (Ln = Y (2) and Gd (3)). The structures of complexes 1 and 2 were established by X-ray diffraction. The reaction of complex 1 with NaBH4 in hexane (20 °C) followed by treatment with dimethoxyethane yielded the unexpected product, { (Me3Si)2NC(NPri)2}Sm(µ3-BH4)2(DME) (5). X-ray diffraction study showed that both borohydride ligands in complex 5 are tridentate.  相似文献   

6.
合成了Cp TiCl2 N[Si(CH3) 3]2 甲基铝氧烷 (MAO)催化体系 ,以该体系进行丙烯聚合得到无规聚丙烯 ,具有高的分子量及良好的弹性 ,玻璃化温度为 - 8 8℃ .产物经DSC、1 3C NMR、DMA等方法表征 .结果表明 ,催化活性随着丙烯压力的增加 ,有明显的增大 .催化活性在 4 0℃下有最高的催化活性 ,而产物分子量随着温度的下降有明显增大 ,在 0℃~ 5 0℃范围内分子量MW =(2 0~ 6 0 )× 10 4 .  相似文献   

7.
The hydrothermal reaction of MoO3, V, Na2WO4· 2H2O, [N(CH2CH2)3N](1,4-diazabicyclo[2.2.2] octane), and H2O at 160°C for 90h gave dark-brown crystals of [HN(CH2CH2)3N]2[HMoVMoVI 5O19]·[N(CH2CH2)3N], (1), in 40% yield. Complex (1) is the first one-electron reduced mixed-valence hexamolybdate to be crystallized and structurally characterized. The crystal structure of (1) consists of discrete [HMoVMoVI 5O19]2– anions, [HN-(CH2CH2)3N]+ cations, and neutral [N(CH2CH2)3N] molecules of crystallization.  相似文献   

8.
在密度泛函理论B3LYP/6-311++G(d,p)及MP2/6-311++G(d,p)水平上研究了单电子锂键复合物Y…Li—CH3[Y=CH3, CH2CH3, CH(CH3)2, C(CH3)3]的结构与性质. 结果表明, 三种单电子锂键复合物H3CH2C…Li—CH3(II), (H3C)2HC…Li—CH3(III)和(H3C)3C…Li—CH3(IV)单电子锂键强度依II(-26.7 kJ·mol-1)相似文献   

9.
The reaction of Gd(BH4)3(THF)2 with two equivalents of sodium N,N′-dicyclohexyl-N″-bis(trimethylsilyl)guanidinate in THF followed by the treatment of the reaction product with 1,2-dimethoxyethane produced the monoguanidinate bis(borohydride) complex [(Me3Si)2NC(NCy)2]Gd(BH4)2DME (1) (Cy is cyclohexyl). The treatment of the heterobimetallic samarium complex {(Me3Si)2NC(NPri)2}2Sm(BH4)2Li(THF)2, in which the lanthanide and lithium atoms are linked by two bridging borohydride groups, with 1,2-dimethoxyethane afforded the ionic complex [{(Me3Si)2NC(NPri)2}2Sm(BH4)2]?[Li(DME)3]+ (2). The structures of complexes 1 and 2 were established by X-ray diffraction. The [(Me3Si)2NC(NCy)2]2Ln(BH4)2Li(THF)2 complexes (Ln = Nd (3), Sm (4), or Yb (5)) were found to catalyze methyl methacrylate polymerization.  相似文献   

10.
Reactions of diiron complexes (E)[5-t-BuC5H3)Fe(CO)]2(-CO)2 [E = Me2Si (1), Me2SiSiMe2 (2), and Me2SiOSiMe2 (3)] with iodine in CHCl3 yielded diiodide complexes (E)[5-t-BuC5H3)Fe(CO)2I]2 [E=Me2Si (5), Me2SiSiMe2 (6), and Me2SiOSiMe2 (7)]. Like (1–3), complexes (5–7) also exists as mixtures of cis and trans isomers even though the Fe–Fe bond in (1–3) has been cleaved. When the pure isomers (1–3) reacted with iodine respectively in CHCl3, the cis isomers (1c–3c) yielded only the cis products (5c–7c), whereas the trans isomers (1t–3t) yielded only the trans isomers (5t–7t). This indicates that iodination of bridged diiron complexes is stereospecific. Similar treatment of trans-(Me2Si)[{5-t-(heptyl)C5H3}Fe(CO)]2(-CO)2 (4t) with iodine gave only the trans product (Me2Si)[{5-t-(heptyl)C5H3}Fe(CO)2I]2 (8t). The molecular structure of (5t) was determined by X-ray diffraction.  相似文献   

11.
12.
通过无水YbCl3和Ph[(CH3)3N]Li在四氢呋喃中反应,合成了目标化合物[Ph(Me3Si)N]3Yb(THF),该化合物经过元素分析,红外光谱以及X单晶结构表征.研究表明该配合物以较高活性催化芳醛的Tischenko反应.  相似文献   

13.
14.
Crystals of [Cr3O(CH3COO)6(H2O)3][UO2(CH3COO)3]·3H2O (I) were synthesized for the first time and studied by X-ray crystallography. The crystals of I are orthorhombic: a = 8.3561(3) ?, b = 16.8421(5) ?, c = 25.7448(9) ?, V = 3623.2(2) ?3, space group P212121, Z = 4, R = 0.0409. The structure is composed of trinuclear [Cr3O(CH3COO)6(H2O)3]+ complexes and mononuclear [UO2(CH3COO)3]? complexes classified with crystal-chemical groups A3M3B 6 2 M 3 1 (A = Cr3+, M3 = O2?, B2 = CH3COO?, M1 = H2O) and AB 3 01 (A = UO 2 2+ , B01 = CH3COO?), respectively. The complexes are bound to each other by electrostatic interactions and hydrogen bonds involving outer-sphere water molecules. The results of IR spectroscopic study of I are in good agreement with the structural data for the crystal.  相似文献   

15.
叶旭  曾兴平  周剑 《化学学报》2016,74(12):984-989
研究考察了在手性(salen)AlCl-叶立德络合物(R,R)-1/2a作为催化剂和异丙醚作为溶剂的条件下,两种不同硅氰化试剂[Me2(CH2Cl)SiCN和Me3SiCN(TMSCN)]在对醛的不对称氰化中的应用情况.一系列不同取代的芳香醛均可分别与这两种试剂发生反应,以高到优秀的产率和对映选择性得到目标产物.脂肪醛的反应产物的对映选择性最高只能达到中等.对比研究发现,Me2(CH2Cl)SiCN在醛的硅氰化反应中显示出了明显高于TMSCN的反应活性,但是产物的对映选择性大体相当.  相似文献   

16.
茂金属配合物[2,5-(Me3Si)2MeC5H2FeI(CO)2]的电子结构研究   总被引:4,自引:0,他引:4  
运用G98W程序,采用Lan12dz基组,对茂金属配合物[2,4-(Me3Si)2MeC5H2F3I(CO)2]进行从头算研究,探讨了配合物结构单元的稳定性,分子轨道能量,原子净电荷布居规律,以及一些前线分子轨道组成特征等,结果表明,标题配合物在能量上可作为结构单元而稳定存在,该结构单元为茂金属配合物的合成,分子组装分析和催化活性研究提供理论依据。  相似文献   

17.
Cs3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)] (I) and Cs5[UO2(CH3COO)3]3[UO2 (NCS)4(H2O)] · 2H2O (II) have been synthesized via the reaction between uranyl acetate and cesium thiocyanate in aqueous solution. According to single-crystal X-ray diffraction data, both compounds crystallize in monoclinic system with the unit cell parameters a = 18.7036(5) Å, b = 16.7787(3) Å, c = 12.9636(3) Å, β = 92.532(1)°, space group C2/c, Z = 4, R = 0.0434 (I); and a = 21.7843(3) Å, b = 24.6436(5) Å, c = 13.1942(2) Å, β = 126.482(1)°, space group Cc, Z = 4, R = 0.0273 (II). Uranium-containing structural units of compound (I) are mononuclear [UO2(CH3COO)3]? and [UO2(CH3COO)(NCS)2(H2O)]? moieties, which correspond to the AB 3 01 and AB01M 3 1 crystallochemical groups (A = UO 2 2+ , B01 = CH3COO?, M1 = NCS? and H2O). The structure of compound II is built of [UO2(CH3COO)3]? and [UO2(NCS)4(H2O)]2? complexes, which belong to the AB 3 01 and AM 5 1 crystallochemical groups, respectively. Uranium-containing complexes in both structures are linked into a framework by hydrogen bonds and electrostatic interactions with cesium cations. The IR spectra of compounds I and II agree well with X-ray diffraction data.  相似文献   

18.
林进  张萍  王昭煜  王宏根 《结构化学》1999,18(3):188-191
用X-射线晶体结构衍射法测定了[C5H4C(CH3)2CH2CH=CH2]Sm(OH)Cl·2MgCl2·4THF的晶体结构。它属三斜晶系,空间群为P^-1,a=10.773(2),b=12.836(3),c=15.478(3)A,a=111.46(3),β=107.71(3),γ=92.54(3)°,V=1868(1)A^3,Mr=827.91,Dx=1.472g/cm^3,μ=2.0006mm  相似文献   

19.
The title compound has been synthesized by the reaction of HgI2 and [(CH3)3- NCH2CH2N(CH3)3]I2 with pH = 7.5 at room temperature, and its crystal structure was determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system, space group P21/c with a = 8.3075(8), b =15.8084(19), c =15.390(2)(°A), β = 95.192(4)o, V = 2012.9(4)(°A)3, Z = 2, Dc = 2.824 g/cm3, F(000) = 1502, C14H39N4O2Hg2I8, Mr = 1711.87, μ(MoKα) = 13.768 mm-1, the final R = 0.0465 and wR = 0.1293 for 3046 observed reflections with I > 2(I). The title compound consists of cations ([C8H22N2]2+) and anion (HgI42-), which are combined by static attracting forces to form the so-called organic-inorganic hybrid material.  相似文献   

20.
The Platinum(II) diamine with N,N-dimethylethylenediamine (N,N-dimeEn) [Pt{(CH3)2N(CH2)2NH2}Cl2] (I) was synthesized. The reaction of the diamine with pyridine gave Pt(II) tetramine [Pt{(CH3)2N(CH2)2NH2}Py2]Cl2 (II), which was oxidized with chlorine to give Pt(IV) triamine Pt{[(CH3)2N(CH2)2}PyCl3]Cl · H2O (III). The reaction of III with chlorine (chloroamidation) yielded chloroimide [Pt{(CH3)2N(CH2)2NCl}PyCl3] (IV). The IR spectra of complexes I–IV and UV/Vis spectra of III and IV were studied. X-Ray diffraction analysis was performed for III (monoclinic crystals, space group P21/c, a = 7.7437(6), b = 8.1100(7), c = 28.52992(2) Å, β = 93.7280(10)°, Z = 4, R hkl = 0.0420) and IV (orthorhombic crystals, space group Pna21, a = 15.7825(12), b = 7.4447(6), c = 12.3099(6) Å, Z = 4, R hkl = 0.0539). During oxidation of Pt(II) tetramine with chlorine, the pyridine molecule is removed from the cis position relative to the (CH3)2N group (trans position relative to the NH2 group) of N,N-dimethylethylenediamine. The reaction of chloroimide complex IV with concentrated HCl (dechloroamidation) at 20°C afforded the initial complex III; that at 100°C, gave triamine III together with Pt(IV) diamine [Pt(N,N-dimeEn)Cl4] (V) (monoclinic crystals, space group P21/n, a = 7.1278(5), b = 11.5384(8), c = 12.7501(9) Å, β = 93.23(10)°, Z = 4, R hkl = 0.0239).  相似文献   

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