富勒烯C60-多芳胺类衍生物选择性加成反应的研究

多芳胺是良好的电子给体,富勒烯C60作为电子受体的光诱导分子内和分子间电荷转移现象[1,2]引起人们普遍关注,尤其是设计合成长寿命电荷分离态的富勒烯C60-多芳胺基类衍生物研究[3,4]是热点课题之一.由于聚吡咯/聚芳胺的氧化还原电位较低[5],我们设想包含吡咯/芳胺给体的富勒烯C60衍生物能延长电荷分离态的寿命.本文用1,3-偶极环加成反应[6]对富勒烯C60与多芳胺化合物的选择性加成反应进行了研究,在不同条件下得到了单加成产物和三加成产物,用FAB-MS,UV-vis,IR,1H NMR,13C NMR,HPLC等方法确定了其分子结构.并且利用半经验AM1量子化学方法在理论上研究了它们的优化构型(如图1)、电子结构,结果表明,富勒烯C60-多芳胺基类衍生物的前沿轨道主要由富勒烯C60部分决定,富勒烯C60母体与功能化基团三苯胺基之间存在较强的分子内电荷转移,这为富勒烯C60衍生物作为光电分子器件材料的应用提供了理论和实验依据.     

醋酸锰作用下二烯丙基叔胺与[60]富勒烯的自由基环加成反应

二烯丙基叔胺与[60]富勒烯在醋酸锰作用下发生自由基环加成反应,生成[60]富勒烯并吡咯烷衍生物.醋酸锰的用量和反应温度等因素对反应有一定影响.反应可能先由Mn(Ⅲ)与烯丙胺经单电子氧化产生自由基,再与[60]富勒烯加成并进一步环化.研究中得到的各产物的结构均通过波谱学方法表征.     

有机富勒烯化合物的逆环加成反应

逆环加成反应是富勒烯衍生物的一种重要反应。在还原、氧化或加热条件下,许多富勒烯衍生物的加成基团会从富勒烯骨架上断开,得到富勒烯母体,是富勒烯环加成反应的逆反应。该反应与富勒烯环加成反应结合,已被应用于富勒烯化学中保护/去保护基团方法,对于选择性制备富勒烯及其衍生物具有重要意义。然而由于逆环加成反应的存在,引起了有机富勒烯化合物的不稳定,从而可能影响其在实际中的应用。最近,我们研究了一系列含有亚胺酯杂原子环结构的富勒烯噁唑衍生物在电化学还原下的稳定性,结果表明加成基团之间存在的分子内C-H…X（X = N,O）氢键对化合物的稳定性可能起着较为关键的作用。在此,我们将结合我们的工作对有机富勒烯化合物的逆环加成反应进行综述。     

2001年全国高中学生化学竞赛（决赛）理论试题答案

第 1题1- 1　Ａ :ＮＨ4 ＨＣＯ3[或 (ＮＨ4 ) 2 ＣＯ3]　Ｂ :ＫＣｌ　Ｃ :Ｋ2 ＳＯ4 　Ｄ :ＮＨ4 Ｃｌ　Ｅ :Ｆｅ2 Ｏ3　Ｆ :ＣＯ21- 2　反应 (1) :(ｍ +ｎ)ＦｅＳＯ4 + 2 (ｍ +ｎ)ＮＨ4 ＨＣＯ3=Ｆｅｍ +ｎ(ＯＨ) 2ｎ(ＣＯ3) ｍ↓ + (ｎ +ｍ) (ＮＨ4 ) 2 ＳＯ4 + (2ｎ +ｍ)ＣＯ2 ↑ +ｍＨ2 ＯＮＨ4 ＨＣＯ3 写成 (ＮＨ4 ) 2 ＣＯ3,Ｆｅｍ +ｎ(ＯＨ) 2ｎ(ＣＯ3) ｍ 写成 (1)Ｆｅ2 (ＯＨ) 4-2ｍ(ＣＯ3) ｍ,(2 )Ｆｅ2 (ＯＨ) 2 ＣＯ3,(3)Ｆｅ(ＯＨ) 2 和ＦｅＣＯ3 且配平的 ,也给分。反应 (2 ) :2Ｆｅｍ +ｎ(ＯＨ) 2ｎ(ＣＯ3) ｍ+ ｍ +ｎ2 Ｏ2…     

C_（60）的胺加成反应和电喷雾电离质谱（ESI－MS）检测

报道了Ｃ６０与１，３－丙二胺和Ｎ，Ｎ－二甲基－１，３－丙二胺的加合反应，反应产物未经预先离子化处理直接用ＥＳＬ－ＭＳ进行检测。由于反应产物从甲苯溶液中析出，避免了生成多胺基加合物，产物以单加成物为主。当加合反应在空气氛下进行时，有加合氧的产物Ｃ６０Ｏｎ（ＮＨ２—ＣＨ２ＣＨ２ＣＨ２ＮＲ２）ｍ（Ｒ＝Ｈ，ＣＨ３）存在。实验发现：Ｎ，Ｎ－二甲基－１，３－丙二胺比１，３－丙二胺更容易与Ｃ６０发生多胺基加成和氧加成反应。通过控制反应条件可制备Ｃ６０二胺的单加成产物。     

邻醌与噁唑的光化[4+4]环加成反应

虽然[2+2]和[4+4]环加成反应都是光化学允许的,但[4+4]环加成远不及[2+2]反应普遍.已知的[4+4]环加成主要为蒽、萘、吡啶-2-酮和吡喃-2-酮衍生物的光化二聚以及它们与某些1,3-二烯的环加成.羰基化合物与烯烃一般发生[2+2]环加成(Peterno-B點hi反应).邻醌和α-二羰基化合物与富电子烯烃则已知可进行[2+2]或[4+2]的光化环加成反应,分别得到α-羰基氧杂环丁烷和1,4-二氧杂环己烯.但未知有光化[4+4]环加成反应.     

过氧化氢氧化-荧光分光光度法测定片剂中叶酸含量

1　引　　言作者曾开发出ＫＭｎＯ4 氧化 荧光分析法测定片剂中叶酸 (ＰＧＡ)含量的荧光新体系。该法通过测定ＰＧＡ的氧化产物蝶呤 6 羧酸的荧光强度 ,间接测定了ＰＧＡ的含量。考虑到用Ｈ2 Ｏ2 氧化ＰＧＡ ,分析其氧化产物蝶呤 6 甲醛的结构 ,也是强荧光性物质 ,也有可能用荧光测定法。为此本文详细研究了在ＮａＡｃ ＨＡｃ和ＮＨ4 Ｃｌ ＮＨ3·Ｈ2 Ｏ不同缓冲溶液中Ｈ2 Ｏ2 氧化ＰＧＡ的最佳条件和荧光特性 ,ＰＧＡ的检测限分别为 5 .2 μｇ/Ｌ(ｐＨ 5 .0 )、6.8μｇ/Ｌ (ｐＨ 10 .5 0 ) ,前者最佳ｐＨ范围较宽 ,抗干扰能力也明显强于…     

Synthesis and structure of {Mo_3S_7[S_2P(OC_2H_5)_2]_3}{Mo_3S_4[S_2P(OC_2H_5)_2]_4(SCN)} and interaction between their cluster units

Ｔｈｅｔｒｉｍｏｌｙｂｄｅｎｕｍｃｌｕｓｔｅｒｓｗｉｔｈｇｅｎｅｒａｌｆｏｒｍｕｌａ[Ｍｏ3(μ3Ｓ)(μＳ)3(μｄｔｐ)(ｄｔｐ)3Ｌ](ｄｔｐ=(Ｓ2Ｐ(ＯＣ2Ｈ5)2)-,Ｌ=Ｈ2Ｏ,ｐｙ,ＳＣ(ＮＨ2)2ｅｔｃ.)[1](ｒｅｆｅｒｒｅｄｔｏａｓＭ1ｔｙｐｅ[2]),ａｎｄ[Ｍｏ3(μ3Ｓ)(μＳ2)3(ｄｔｐ)3]Ｘ(Ｘ=Ｃｌ,Ｉ)[3](ｒｅｆｅｒｒｅｄｔｏａｓＭ2ｔｙｐｅ),ａｒｅｔｗｏｍａｉｎｔｙｐｅｓｏｆｔｒｉｍｏｌｙｂｄｅｎｕｍｃｌｕｓｔｅｒｓｅｖｅｒｉｎｖｅｓｔｉｇａｔｅｄｂｙｏｕｒｒｅｓｅａｒｃｈｇｒｏｕｐ.Ａｓｗｅｈａｖｅａｌｒｅａｄｙ…     

NaF-SnCl_2光度法测定磷的方法中,钼磷黄还原为钼磷蓝的反应式应如何表述?

答 :关于钼磷杂多酸还原为钼磷蓝的反应式一般表示为 :(ＮＨ4 ) 3 Ｈ4 [ＰＭｏ2 Ｏ7) 6]+2ＳｎＣｌ2 +4ＨＣｌ　　　　　　 (ＮＨ4 ) 3 Ｈ4 [Ｐ(Ｍｏ2 Ｏ5)·5 (Ｍｏ2 Ｏ7) ]+2ＳｎＣｌ4 +2Ｈ2 Ｏ但有报道认为在有ＮａＦ存在下 ,反应中不可能有ＳｎＣｌ4 或ＳｎＣｌ2 - 6的形式的化合状态 ,因为ＳｎＦ2 - 6的积累稳定常数的对数值ｌｇβ6等于 2 5 ,远高于ＳｎＣｌ2 - 6的积累稳定常数的对数值 (ｌｇβ6=14)。此外 ,一般认为磷钼蓝分子中只有 2个Ｍｏ(Ⅵ )被还原为Ｍｏ(Ⅴ )。但用光度滴定法研究钼磷蓝的结果表明在 12个Ｍｏ(Ⅵ )中有 4个Ｍ…     

烯醇硅醚对[60]富勒烯的亲核加成反应

在空气气氛和非极性溶剂(甲苯)中1-(4'-甲氧基苯基)-1-三甲基硅氧基乙烯与[60]富勒烯反应得到了非预计的环丙基骈[60]富勒烯衍生物(5).在无氧和极性非质子性溶剂(THF)中进行上述反应,得到了1,2-取代[60]富勒烯亲核加成产物(3)。对反应的机理作了合理的阐述。     

Synthesis and X-ray structure of the Mo(VI) species Mo4O12(C12H30N4S2)2(C3H7ON)n (n ≈ 2)

Dissolution of Mo₂O₅((CH₃)₂NCH₂CH₂NHCH₂CH₂S)₂ in dimethylformamide results in the formation of a species without coordinated sulphur, as indicated by ⁹⁵Mo NMR spectroscopy. Subsequent crystallization of this solution yielded the compound Mo₄O₁₂(C₁₂H₃₀N₄S₂)₂(C₃H₇ON)₂ which X-ray crystallography shows to consist of a novel Mo₄O₁₂ core, containing an eight-membered Mo₄O₄ ring with the two pairs of diagonal molybdenum atoms linked by disulphido-containing groups.     

Anionic derivatives of pentafluoro-λ-sulfanyl (fluorosulfonyl) acetic acid esters

New ester salts [R₃NH]⁺[F₅SC(SO₂F)C(O)OR′]⁻ where RH, CH₃CH₂ and R′CH₃,(CH₃)₂CH have been prepared from corresponding esters and amines. The sodiumsalt Na[F₅SC(SO₂F)C(O)OCH(CH₃)₂] was used to prepare the following -substitutedderivatives: SF₅CX(SO₂F)C(O)OCH(CH₃)₂, XBr, Cl. The crystal structure of[(C₂H₅)₃NH]⁺[F₅SC(SO₂F)C(O)OCH₃]⁻ was determined and is monoclinic: P2₁/n;a=8.758(2) Å, b=9.645(2) Å and c=19.167(4) Å; β=97.92(3)°; V=1603.6 ų; Z=4.     

Theoretical study on magnetic coupling interaction for Cu(II) binuclear systems with extended bridging groups

The magnetic coupling interaction for Cu(II) binuclear systems with bridging groups C₂O₄²⁻, C₂O₂(NH)₂²⁻ (cis), C₂O₂(NH)₂²⁻ (trans) and C₂S₂(NH)₂²⁻ (trans) was studied by the broken symmetry (BS) approach within the framework of the density functional theory (DFT). The influence of different coordination atoms and geometry on magnetic coupling interaction was theoretically analyzed. Both of the calculated and experimental results were compared. The variation trends of coupling interaction calculated are in agreement with experimental ones.     

Semiempirical molecular dynamics studies of C60/C70 fullerene oxides: C60O, C60O2 and C70O

The spectral analysis indicates that all isomers of C₆₀O, C₇₀O and C₆₀O₂ have an epoxide-like structure (an oxygen atom bridging across a C–C bond). According to the geometrical structure analysis, there are two isomers of fullerene monoxide C₆₀O (the 5,6 bond and the 6,6 bond), eight isomers of fullerene monoxide C₇₀O and eight isomers of fullerene dioxide C₆₀O₂. In order to simulate the real reaction conditions at 300 K, the calculation of the different isomers of C₆₀O, C₆₀O₂ and C₇₀O fullerene oxides was carried out using the semiempirical molecular dynamics method with two different approaches: (a) consideration of the geometries and thermodynamic stabilities, and (b) consideration of the ozonolysis mechanism. According to the semiempirical molecular dynamic calculation analysis, the probable product of this ozonolysis reaction is C₆₀O with oxygen bridging over the 6–6 bond (C_2v). The most probable product in this reaction contains oxygen bridging across in the upper part of C₇₀ (6–6 bond in C₇₀O-2 or C₇₀O-4) an epoxide-like structure. C₆₀O₂-1, C₆₀O₂-3 and C₆₀O₂-5 are the most probable products for the fullerene dioxides. All of these reaction products are consistent with the experimental results. It is confirmed that the calculation results with the semiempirical molecular dynamics method are close to the experimental work. The semiempirical molecular dynamics method can offer both the reaction temperature effect by molecular dynamics and electronic structure, dipole moment by quantum chemistry calculation.     

The reaction of cis dioxobis(2,4 pentanedionato)molybdenum (VI) and 2,2′ pyridylbenzoxazole (L), a novel route to β[Mo8O26]

MoO₂(C₅H₇O₂)₂, where C₅H₇O₂ is 2,4-pentanedione (acac), reacts with 2-2′ pyridylbenzoxazole in acetone to give a product with stoichiometry, Mo₃C₂₄H₁₆N₆O₁₂. This product dissolves readily in dimethylformamide to give a brown solution which on standing for several weeks yielded crystals. An X-ray structure determination showed these crystals to contain uncoordinated 2-2′pyridylbenzoxazole and [(CH₃)₂NH₂]₄⁺[Mo₈O₂₆]⁴⁻.     

Synthesis, reaction and structure of a series of chromium(III) complexes containing oxalate ligand

A series of chromium(III) complexes [Cr(bipy)(HC₂O₄)₂]Cl·3H₂O (1), [Cr(phen)(HC₂O₄)₂]Cl·3H₂O (2), [Cr(phen)₂(C₂O₄)]ClO₄ (3), [Cr₂(bipy)₄(C₂O₄)](SO₄)·(bipy)_0.5·H₂O (4) and [Mn(phen)₂(H₂O)₂]₂[Cr(phen)(C₂O₄)₂]₃ClO₄·14H₂O (5) were synthesized (bipy=4,4′-bipyridine, phen=1,10-phenanthroline), while the crystal structures of 1 and 3–5 have been determined by X-ray analysis. 1 and 3 are mononuclear complexes, 4 contains binuclear chromium(III) ions and 5 is a 3D supromolecule formed by complicated hydrogen bonding. 1–3 are potential molecular bricks of chromium(III) building blocks for synthesis heterometallic complexes. When we use these molecular bricks as ligands to react with other metal salts, unexpected complexes 4 and 5 are isolated in water solution. The synthesis conditions and reaction results are also discussed.     

Chemie polyfunktioneller moleküle : LXXXVII. Synthese und reaktionsverhalten von 4-methyl-1,2,6-tristiba-tricyclo[2.2.1.0]heptan (Sb3-nortricyclan) gegenüber chrom-, molybdän- und wolframhexacarbonyl

The reaction of CH₃C(CH₂Cl)₃ and NaSb(C₆H₅)₂ in liquid ammonia leads to Sb₂(C₆H₅)₄ (I). Using CH₃C(CH₂Br)₃ instead of CH₃C(CH₂Cl)₃ results in the formation of I and CH₃C[CH₂Sb(C₆H₅)₂]₃ (II). Treatment of II with gaseous HCl in dry CH₂Cl₂ yields CH₃C(CH₂SbCl₂)₃ (III) under elimination of benzene. The reduction of III with Na in THF gives the first all-cis-organocyclotristibane (Sb₃-nortricyclane) CH₃C(CH₂Sb)₃ (IV) which forms the new CH₃C(CH₂Sb)₃M(CO)₅ complexes (Va---Vc) with M(CO)₅THF (M = Cr, Mo, W).     

Two Pentavanadate-based Organic-inorganic Materials with Third-order NLO Properties

Two isolated organic-inorganic pentavanadate-based hybrids,[H2N(CH3)2]6.34[V^V(μ3-O)4V4^IVO5(SO4)4]·(SO4)0.67·(DMF)·[HN(CH3)2]1.66(1)and [(HN)2(CH2)2(CH3)4][V^V(μ3-O)4V4^IVO5(SO4)4][H2N(CH3)2]3@(DMF)@ [HN(CH3)2]0.5(2)(DMF=N,N-dimethylformamide)have been synthesized under solvothermal conditions and structurally characterized.In compound 1,three adjacent basic units form a triangle type cluster.The symmetric double-layer exists in compound 2.The study of the third-order nonlinear optical(NLO)properties for the two compounds demonstrates that the two-photon absorption(TPA)cross-section σ values of compounds 1 and 2 are 1372 and 1228 GM,respectively,indicating that both compounds may have potential application in optical field.     

Dimethylchalkogenide als liganden in kationischen cyclopentadienyleisen-bis(phosphin)-komplexen: synthese, reaktivität und kristallstruktur von [C5H5Fe(P(OCH3)3)2(S(CH3)2)]PF6

Thermal displacement of coordinated nitriles RCN (R = CH₃, C₂H₅ or n-C₃H₇) in [C₅H₅Fe(L₂)(NCR)]X complexes (L₂ = P(OCH₃)₃)₂, (P(OC₆H₅)₃)₂ or (C₆H₅)₂PC₂H₄P(C₆H₅)₂ (DPPE)) by E(CH₃)₂ affords high yields of [C₅H₅Fe(L₂)(E(CH₃)₂)]X compounds (E = S, Se and Te; X = BF₄ or PF₆). Spectroscopic data and ligand displacement reactions are presented and discussed together with related observations on [C₅H₅Fe(CO)₂(E(CH₃)₂)]BF₄ compounds. The molecular structure of [C₅H₅Fe(P(OCH₃)₃)₂(S(CH₃)₂)]PF₆ was determined by a single-crystal X-ray diffraction study: monoclinic, space group P2₁/n-C⁵_2h (No. 14) with a = 8.4064(12), b = 11.183(2), c = 50.726(8) Å, β = 90.672(13)° and Z = 8 molecules per unit cell. The coordination sphere of the iron atom is pseudo-tetrahedral with an Fe---S bond distance of 2.238 Å.     

Crystallization of Ammonium Nitrate Under Organised Monolayers at Air-Aqueous Interface

The crystallization of NH₄NO₃ under compressed Langmuir monolayers of carboxybe-taine(C₂₂N₃COO^-),C₂₂H₁₅N(CH₂)₃(CH₂)₃COO^--[C₂₂N₃COO^-] and dioleoyl-L-a-lecithin(DOPC) was studied by means of π-A. ΔV-A and fluorescence microscopy (FM). The surface pressure, surface potential and molecular area of C₂₂N₃COO^- were decreased on the NH₄NO₃ solution subphase. The surface pressure and molecular area of DOPC was increased. The surface potential of DOPC was decreased. We can directly observe the surface crystallization of NH₄NO₃ by FM. The results revaled that C₂₂N₃COO^- monolayer was the promoter of NH₄NO₃ surface crystallization. In contrast,DOPC monolayer was the inhibitor of the surface crystallization of NH₄NO₃.