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1.
C60的胺加成反应和电喷雾电离质谱(ESI—MS)检测   总被引:2,自引:0,他引:2  
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ESI-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  相似文献   

2.
用INDO系列方法对C^2-60与CH3反应的中间体C60(CH3)^-进行理论研究。得到具有C,对称性的构型,结果表明,CH3加成到C15上,将使与共相邻的双键碳(C30)的电荷密度和自旋密度达极大值,故加成反应部位在C30处;另外,C15的对位C12也较其它部位易于反应,且有两个反应场所,因而产物C60(CH3)2可能为六元环上的1,2-加成和1,4-加成两种异构体的混合物,同时对两种加成产物  相似文献   

3.
Co2(CO8)分别与4种硫代乙内酰脲S=CNHC(O)C(R1)(R2)N(COR3)反就,得到4个新的含硫代乙内酰脲桥基双齿配位的三核钴羰基硫族合物。用元素分析、IR、^1H NMR和MS等手段表征了它们的结构,用X射线衍射测定了其中一个族合物Co3(CO7)7(μ3-S)[μ,η^2-SCNC(O)C(CH3)(CH3)N(COCH3)](Ⅳ)的晶体结构,晶体属三斜晶系,P1↑-空间群,晶胞  相似文献   

4.
采用NMR方法考察了室温和低温(-78~-60℃)下Pd2X2(dpm)2(X=NCO-,CH3CO,SCN-和NO,dpm=Ph2PCH2PPh2)与H2S在CD2Cl2或CDCl3中的反应。结果表明,在X=NCO-和CH3CO的情况下,H2S优先与这些Pd配合物的阴离子作用生成相应的共轭酸HX和Pd2(SH)2(dpm)2,后者在H2S存在下又进一步转化为Pd2(SH)2(dpm)2(μ-S);当X=SCN-和NO时,反应则生成结构可能为[Pd2(H)(SH)(μ-SH)(dpm)2]+的双核Pd配合物。  相似文献   

5.
采用NMR方法考察了室温和低温(-78~-60℃)下Pd2X2(dpm)2(X=NCO^-,CH3CO^-2,SCN^-和NO^-3,dpm=Ph2PCH2PPh2)与H2S在CD2Cl2或CDCl3中的反应。结果表明,在X=NCO^-和CH3CO^-2的情况下,H2S优先与这些Pd配合物的阴离子作用生成相应的共轭酸HX和Pd2(SH)2(dpm)2,后者在H2S存在下又进一步转化为Pd2(SH)  相似文献   

6.
以2-(3,4-环己基类二氧-5-异丙基)苯基乙醇(2)和3-异丙氧基-5,5-二甲基-1,3-环己烯酮(4)为原料,利用羰基α-位的烷基化反应和分子内的Friedel-Carfts反应为关键步骤,经9步反应,合成了多氧芳香型三环二萜类天然产物Salvinolone。  相似文献   

7.
无水三氯化稀土(LnCl3),二(三甲硅基)胺基钾(LiN(SiMe3)2〗及1-(2-甲乙基)茚室温上在四氢呋喃溶剂中反应,得到了4个含1-(2-甲氧乙基)茚基和二(三甲硅基)胺基的稀土金属有机物{(C9H6CH2C2OMe)Ln〖N(SiMe3)2〗2(Ln=Nd,Sm,Dy,Yb)},这些配合物均经元素分析、IR和MS表征。  相似文献   

8.
首次合成了30种新型O-(1-甲硫基乙叉胺基)磷酰胺酯及磷酸酯类化合物,生物活性测定表明,部分化合物具有一定的杀菌和除草活性,化合物(R^1O)2O(O)-ON=C9SCH3)CH3具有一定的杀虫活性。  相似文献   

9.
首次报道了一个新的拟酶模型物-双[N,N'-1,2-亚乙基-2,2'-(苯基亚甲基)二(3,4-二甲基吡咯-5-醋缩亚胺)]合双锰的合成方法及光谱特征;并对用PhIO单加氧化环己烷反应的催化性能及自氧化反应进行了研究。结果表明,此Schiff碱双锰配合物的催化性能及稳定性与金属卟啉TPPMnCl相似。  相似文献   

10.
Co3(CO)7(μ3—S)(μ,η^2—SCNR2)的合成和晶体结构   总被引:1,自引:0,他引:1  
Co2(CO)8与4个二硫代双(烷基硫代甲酰胺)类前配体[R2NC(S)S]2反应,得4个含烷基硫代甲酰胺基的三核钴羰基硫簇合物。通过元素分析、IR、^1HNMR和MS等方法表征了它们的结构,用X射线衍射法测定了其中一个簇合物Co3(CO)7(μ3-S)[μ,η^2-SCN(i-Pr)2](Ⅲ)的晶体结构。晶体属单斜晶系,P21/n空间群,晶胞参数a=1.1452(2)nm,b=1.5028(3)  相似文献   

11.
Reactions of alpha-hydroxyalkyl radicals with 3,5-pyridinedicarboxylic acid (3,5-PDCA) and nicotinic acid (NA) were studied at appropriate pHs in aqueous solutions by pulse radiolysis technique. At pH 1, CH(3)C*HOH and *CH(2)OH radicals were found to react with 3,5-PDCA by rate constants of 2.2 x 10(9) and 5.1 x 10(8) dm(3) mol(-1) s(-1), respectively, giving radical adduct species. The adduct species formed in the reaction of CH(3)C*HOH radicals with 3,5-PDCA underwent unimolecular decay (k = 9.8 x 10(4) s(-1)) giving pyridinyl radicals. Reaction of (CH(3))(2)C*OH, CH(3)C*HOH, and *CH(2)OH radicals with NA at pH 3.3 gave the adduct species which subsequently decayed to the pyridinyl radicals. At pH 1, wherein NA is present in the protonated form, (CH(3))(2)C*OH radicals directly transfer electrons to NA, whereas CH(3)C*HOH and *CH(2)OH radicals react with higher rate constants compared with those at pH 3.3, initially giving the adduct species which subsequently undergo elimination reaction giving pyridinyl radicals. Reactions of alpha-hydroxyalkyl radicals with 3,5-pyridinedicarboxylic acid and nicotinic acid are found to proceed by an addition-elimination pathway that provides one of the few examples of organic inner sphere electron-transfer reactions. Rate constant for the addition reaction as well as rate of elimination varies with the reduction potential of alpha-hydroxyalkyl radicals.  相似文献   

12.
The reaction of (C(6)F(5))(2)BH (1) with N,N-dimethylallylamine (2), N,N-diethylallylamine (3) and 1-allylpiperidine (4) afforded the five-membered ring systems (C(6)F(5))(2)B(CH(2))(3)NR(2) (R = Me (5), Et (6)) and (C(6)F(5))(2)B(CH(2))(3)N(CH(2))(5) (7) with an intramolecular dative B-N bond. A different product was obtained from the reaction of (C(6)F(5))(2)BH (1) with N,N-diisopropylallylamine (8), which afforded the seven-membered ring system (C(6)F(5))(2)B(CH(2))(3)N(iPr)CH(Me)CH(2) (9) under extrusion of dihydrogen. All compounds were characterised by elemental analysis, NMR spectroscopy and single-crystal X-ray diffraction experiments. Density functional theory (DFT) studies were performed to rationalise the different reaction mechanism for the formation of products 6 and 9. The bonding situation of compound 9 was analysed in terms of its electron density topology to describe the delocalised nature of a borane-enamine adduct.  相似文献   

13.
The methyl cation and CF(3)(+) attack saturated, acyclic ketones to make vibrationally excited adduct ions. Despite their high internal energies and short lifetimes, these adducts undergo deep-seated rearrangements that parallel slower processes in solution. Observed pathways include alkene and alkane expulsions, in addition to (in the case of CF(3)(+)) the precedented loss of CF(2)O + HF. For the vast majority of ketones, the principal charged products are the CF(3)(+) adducts of lighter carbonyl compounds, ions that are not easily prepared by other avenues. Evidence for ion structures comes from collisionally activated unimolecular decomposition and bimolecular ion-molecule reactions. Typical examples are di-n-propyl and diisopropyl ketones (both of which produce CH(3)CH=OCF(3)(+) as the principal ion-molecule reaction product) and pentamethylacetone (which produces (CH(3))(2)C=OCF(3)(+) as virtually the sole ion-molecule reaction product). Isotopic labeling experiments account for mechanisms, and DFT calculations provide a qualitative explanation for the relative abundances of products from unimolecular decompositions of the chemically activated CF(3)(+) adduct ions that are initially formed.  相似文献   

14.
Laser-induced fluorescence from the CH3I-Cl and ICH2I-Cl adducts formed in association reactions between chlorine atoms and CH3I and CH2I2 has been observed for the first time. The LIF excitation and dispersed fluorescence spectra have been measured in the range 345-375 nm and 380-480 nm, respectively, at 204 and 296 K. The excitation spectra exhibit vibrational fine structure, and a semiquantitative analysis of the spectra yields a similar binding energy for both adducts of approximately 60 kJ mol(-1). The adduct fluorescence is efficiently quenched by N2 and exhibits a zero-pressure lifetime of approximately 25-30 ns. Using LIF excited from the CH3I-Cl and ICH2I-Cl adducts, the kinetics of the reactions of atomic chlorine with methyl iodide and diiodomethane have been investigated, the results showing that both reactions proceed via two independent channels, an association reaction to form the adduct and a bimolecular abstraction reaction. At T approximately 200 K, the association reaction is predominant, and CH3I-Cl formation is irreversible, with rate coefficients for adduct formation found to be pressure-dependent and in reasonable agreement with the literature. At approximately 200 K, removal of the adduct is dominated by reaction with radical species (CH3 and ClSO) and by self-reaction, which proceed at close to the gas kinetic limit. At 296 K, CH3I-Cl formation is reversible, and the equilibrium constant, K(p) = (70.9 +/- 27.4) x 10(3) atm(-1), was determined, which is in excellent agreement with the literature, and the adduct does not significantly react with CH3I. The uncertainty is at the 95% confidence level (2sigma) and includes systematic errors. At approximately 200 K, the ICH2I-Cl adduct is again stabilized, with pressure-dependent rate coefficients reaching the high pressure limit at lower pressures than for the Cl + CH3I reaction. At room temperature, the ICH2I-Cl adduct is removed via an additional unimolecular decomposition channel, which dominates over the reversible decomposition channel to reform Cl + CH2I2. Neither adduct was observed to undergo significant reaction with molecular oxygen at approximately 200 or 296 K, with an upper limit rate coefficient determined as k < 10(-16) cm(3) molecule(-1) s(-1).  相似文献   

15.
It has previously been demonstrated that both [(C5Me5)Ir(PMe3)(CH=CH2)H] and [(C5Me5)Ir(PMe3)(H2C=CH2)] are formed when [(C5Me5)Ir(PMe3)] is thermolytically generated in the presence of ethylene. At higher temperatures, the vinyl hydride is converted to the eta2-ethylene adduct. Density functional theory has now been used to investigate this reaction, using the B3LYP functional, two types of basis sets (LanL2DZ and TZV*), and two models of the [(C5R5)Ir(PR3)] species (R=H and CH3). The study consists of full optimizations of local minima, first-order saddle points, and minimum energy crossing points (MECP). The experimental results are best accounted for by considering both singlet and triplet spin surfaces. The relative energies of singlet [(C5R5)Ir(PR3)(CH3)H], [(C5R5)Ir(PR3)(CH=CH2)H], and [(C5R5)Ir(PR3)(H2C=CH2)] are in good agreement with experiment, as is the calculated barrier for the conversion from the vinyl hydride to the eta2-alkene complex. However, the singlet surface alone fails to explain the experimentally observed product ratio, or the intermediate inferred from experimental isotope effect studies. Locating the MECP between singlet and triplet surfaces indicates that the thermolysis of the singlet alkyl hydride precursor directly forms triplet [(C5R5)Ir(PR3)]. The weak vanderWaals adduct of triplet [(C5R5)Ir(PR3)] and ethylene is proposed to be the key intermediate in the overall reaction. The interchanging of the available ethylene C-H bonds in this triplet sigma complex accounts for the observed kinetic isotope effects, and partitioning between alkene pi-complexation and C-H bond activation may also occur from this common intermediate. The possible role of steric factors and molecular dynamics are also discussed.  相似文献   

16.
用INDO系列方法对C602-与CH3反应的中间体C60(CH3)-进行理论研究,得到具有Cs对称性的构型。结果表明,CH3加成到C15上,将使与其相邻的双键碳(C30)的电荷密度和自旋密度达极大值,故加成反应部位在C30处;另外,C15的对位C12(或C27)也较其它部位易于反应,且有两个反应场所,因而产物C60(CH3)2可能为六元环上的1,2-加成和1,4-加成两种异构体的混合物。同时对两种加成产物的结构和电子光谱进行了理论研究,指认其电子跃迁,并讨论了其光谱红移的原因。  相似文献   

17.
The reactions of Cl atoms with XCH2I (X = H, CH3, Cl, Br, I) have been studied using cavity ring-down spectroscopy in 25-125 Torr total pressure of N2 diluent at 250 K. Formation of the XCH2I-Cl adduct is the dominant channel in all reactions. The visible absorption spectrum of the XCH2I-Cl adduct was recorded at 405-632 nm. Absorption cross-sections at 435 nm are as follows (in units of 10(-18) cm2 molecule(-1)): 12 for CH3I, 21 for CH3CH2I, 3.7 for CH2ICl, 7.1 for CH2IBr, and 3.7 for CH2I2. Rate constants for the reaction of Cl with CH3I were determined from rise profiles of the CH3I-Cl adduct. k(Cl + CH3I) increases from (0.4 +/- 0.1) x 10(-11) at 25 Torr to (2.0 +/- 0.3) x 10(-11) cm3 molecule(-1) s(-1) at 125 Torr of N2 diluent. There is no discernible reaction of the CH3I-Cl adduct with 5-10 Torr of O2. Evidence for the formation of an adduct following the reaction of Cl atoms with CF3I and CH3Br was sought but not found. Absorption attributable to the formation of the XCH2I-Cl adduct following the reaction of Cl atoms with XCH2I (X = H, CH3, Br, I) was measured as a function of temperature over the range 250-320 K.  相似文献   

18.
The reaction of the alpha-hydroxyalkyl radical of 2-propanol (1-hydroxy-1-methylethyl radical) with nitrite ions was characterized. A product of the reaction was assigned as the adduct nitro radical anion, [HO-C(CH(3))(2)NO(2)](*-). This radical was identified using time-resolved electron spin resonance (TRESR). The radical's magnetic parameters, the nitrogen hyperfine coupling constant (a(N) = 26.39 G), and its g-factor (2.0052) were the same as those of the nitro radical anion previously discovered in (*)OH spin-trapping experiments with the aci-anion of (CH(3))(2)CHNO(2). Production of [HO-C(CH(3))(2)NO(2)](*-) was determined to be 38% +/- 4% of the reaction of (CH(3))(2)C(*)-OH with nitrite. The reason why this fraction was less than 100% was rationalized by invoking the competitive addition at oxygen, which forms [HO-C(CH(3))(2)ONO](*-), followed by a rapid loss of (*)NO. Furthermore, by taking this mechanism into account, the bimolecular rate constant for the total reaction of (CH(3))(2)C(*)-OH with nitrite at reaction pH 7 was determined to be 1.6 x 10(6) M(-1) s(-1), using both decay traces of (CH(3))(2)C(*)-OH and growth traces of [HO-C(CH(3))(2)NO(2)](*-). This correspondence further confirms the nature of the reaction. The reaction mechanism is discussed with guidance by computations using density functional theory.  相似文献   

19.
C~6~0与偶氮二异丁腈基自由基反应的ESR研究   总被引:1,自引:0,他引:1  
陈晓宇  吴鸣飞  韩钰  戚苓  徐正 《有机化学》1996,16(5):453-455
C~6~0与偶氮二异丁基腈热分解产生的游离基(CH~3)~2CCN发生加成反应, 产物的红外光谱出现C~6~0和CN, CH的特征振动峰, ESR谱出现一对弱的肩峰, 中间的主峰容易功率饱和, 表明有两类物种存在, 提出了可能的反应机理。  相似文献   

20.
自宏观量合成和分离C60以来,人们不断地合成各种功能化的C60衍生物.在对C60化学性质的认识过程中,气相离子化学一直起着十分重要的作用。  相似文献   

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