p,p′-芳炔桥连的四联萘拓扑环芳分子的设计与合成

基于联萘衍生物手性构型高度稳定的特点, 以光学活性的(R)-2,2'-二乙炔基-1,1'-联萘为模板, 设计了3个有趣的拓扑环芳分子——含有4个手性联萘单元的(R,R,R,R)-2a～2c, 并探讨了它们的合成. 合成路线涉及三甲基硅(Me₃Si-)保护基的控制导入, 对位取代的芳基连接桥的链接, 保护基的脱去以及分子间偶合成环4个步骤. 用比旋光度([α]_D), MS, IR, UV-Vis, ¹H和¹³C NMR以及元素分析表征了这些化合物.     

N-烷基-N-酰基磺酰胺聚苯乙烯基微球作为固相酰化剂的研究

一种可循环使用的固相试剂：N-烷基-N-酰基磺酰胺聚苯乙烯基微球(5), 通过对聚苯乙烯磺酰氯微球树脂进行两步功能基化的修饰反应来制备. 制备过程如下：聚苯磺酰氯树脂(1)与伯胺(2)反应得到聚苯乙烯基N-烷基磺酰胺树脂(3), 树脂3用酰氯(4)或酸酐酰化得到N-烷基-N-酰基磺酰胺聚苯乙烯基树脂(5). 酰化的树脂5作为酰基转移试剂与亲核试剂胺反应得到二级酰胺. 根据5上取代基对酰胺生成的程度的影响结果表明, 烷基R¹和酰基(R²CO)对酰基转移反应活性的大小依次分别为：苯基＞苄基＞甲基＞正丁基＞＞H和对硝基苯甲酰基(苯甲酰基＞乙酰基. 胺的亲核能力对酰胺的收率也有一定的影响. N-苯基-N-苯甲酰基磺酰胺树脂重复使用3次没有发现活性降低.     

1-(2,6-二氯-4-三氟甲基苯基)-3-氰基-5-氨基吡唑及其磺酰胺的合成及晶体结构

2,6-二氯-4-三氟甲基苯胺经重氮化后与2,3-二氰基丙酸酯反应合成了1-(2,6-二氯-4-三氟甲基苯基)-3-氰基-5-氨基吡唑(1), 1与苯磺酰氯、对甲基苯磺酰氯、甲基磺酰氯反应, 得到1的苯磺酰胺2a、对甲基苯磺酰胺2b和双甲基磺酰胺2c. 通过元素分析、红外光谱、核磁共振氢谱、核磁共振碳谱、质谱等手段对其结构进行了表征. 用X射线单晶衍射测定了化合物1, 2a和2c的晶体结构. 1属于正交斜方晶系, Pbca空间群, 晶胞参数 a＝1.61739(7) nm, b＝1.62480(7) nm, c＝3.10857(13) nm, ＝＝＝90, V＝8.1691 nm³, Z＝24, R＝0.1089, wR＝0.2545. 2a属于单斜晶系, C2/c空间群, 晶胞参数 a＝3.35144(18) nm, b＝0.97948(5) nm, c＝2.44717(12) nm, β＝102.460(1), V＝7.8440(7) nm³, Z＝8, R＝0.1831, wR＝0.2600. 2c属于三斜晶系, P-1空间群, 晶胞参数 a＝0.84681(7) nm, b＝0.89652(83) nm, c＝1.43497(12) nm, α＝75.198(2), β＝87.918(1), γ＝65.395(1), V＝0.9546 nm³, Z＝2, R＝0.049, wR＝0.135.     

二维Co(nip)2(py)2(H2O)2配合物的水热合成, 晶体结构和热分解机理研究(nip＝5-硝基间苯二甲酸根, py＝吡啶)

用水热法以5-硝基间苯二甲酸和吡啶为配体合成并培养了Co(nip)₂(py)₂(H₂O)₂的单晶. 对单晶进行了X射线单晶衍射分析、元素分析、傅里叶变换红外光谱分析、差热分析和热重-微商热重分析. 该配合物晶体为单斜晶系, 属于P2(1)/c空间群. 晶胞参数为a＝1.1662(3) nm, b＝1.7734(4) nm, c＝0.6988(2) nm, β＝102.46(4)°, V＝1.4112(6) nm³, Z＝2, D_c＝1.585 Mg/m³, μ(Mo Kα)＝0.688 mm^－1. 所有晶体数据的R因子为: R₁＝0.1064, wR₂＝0.1270; 最终R因子[I＞2σ(I)]为: R₁＝0.0467, wR₂＝0.1008. X射线单晶衍射分析的结果表明, 依靠分子内氢键、分子间氢键、硝基氧之间的弱相互作用以及π-π堆积作用, 配合物分子被连成二维无限平面结构. 根据配合物的热分析结果, 配合物及热分析各阶段残渣的傅里叶变换红外光谱, 我们推测出了配合物的热分解机理.     

基态N2O－的势能函数研究

以6-311＋＋G(3df, 3pd)为基函数, 采用密度泛函理论的B3LYP方法对N₂O^－分子体系的结构进行了优化计算. 结果表明N₂O^－分子最稳态为C_s构型, 电子组态为²A', 平衡核间距R_N—N＝0.11873 nm, R_N—O＝0.13012 nm, 键角∠NNO＝133.94448°, 离解能D_e＝10.3857 eV, 基态简正振动频率: 弯曲振动频率ν₁＝656.7488 cm^－1, 对称伸缩振动频率ν₂＝998.1562 cm^－1, 反对称伸缩振动频率ν₃＝1684.3093 cm^－1. 并用多体展式理论方法推导出了基态N₂O^－分子的分析势能函数, 其等值势能图准确地再现了N₂O^－分子的结构特征和离解能.     

β-环糊精与水杨酸包合物的合成与结构

合成了β-环糊精与水杨酸的包合物b-cyclodextrin-salicylic acid (β-CD-sal) [(C₄₂H₇₀O₃₅)₂•(C₇H₆O₃)₂•(H₂O)₂₄], 用X射线单晶衍射、元素分析和核磁共振对其分子结构进行了表征. X射线单晶衍射结果表明: 包合物的晶体属于单斜晶系, 空间群为C₂, a＝1.9269(5) nm, b＝2.4395(7) nm, c＝1.6095(4) nm, β＝107.816(5)°, V＝7.203(3) nm³, Z＝4, D_c＝1.373 g•cm^－3, F(000)＝3176, R[I＞2σ(I)]＝0.0971. 在形成的2∶2包合物中, β-环糊精通过羟基间的氢键形成头对头的二聚体, 两个水杨酸分子以不同的形式与环糊精形成包合物, 其中一个水杨酸分子寄居于环糊精的空腔中, 而另一个水杨酸则位于由两个环糊精形成二聚体的空隙中.     

手性3,5-二甲基-2-芳基-2-吗啉醇盐酸盐的合成及其晶体结构

以(S)-2-氨基丙醇为手性源与α-溴-3-氯苯丙酮反应, (R)-2-氨基丙醇为手性源与6-甲氧基-2-(2-溴丙酰基)萘反应, 分别合成了手性纯化合物(2R,3R,5S)-3,5-二甲基-2-(3-氯苯基)-2-吗啉醇盐酸盐(4a)和(2S,3S,5R)-3,5-二甲基-2-(6-甲氧基-2-萘基)-2-吗啉醇盐酸盐(4b), 利用X射线单晶衍射仪测定了两化合物的晶体结构和两化合物的空间结构, 并初步分析两化合物空间结构, 化合物4a晶体属正交晶系, 空间群为P2₁2₁2, 晶胞参数为: a＝0.8718(2) nm, b＝0.7883(2) nm, c＝2.0247(6) nm, Z＝4, V＝1.3915(7) nm³, D_c＝1.328 g/cm³, F(000)＝584, R₁＝0.0399, wR₂＝0.0797, S＝1.042. 化合物4b晶体属正交晶系, 空间群为P2₁2₁2₁, 晶胞参数为: a＝0.71035 (9) nm, b＝0.77703(10) nm, c＝2.9820(4) nm, Z＝4, V＝1.6318(4) nm³, D_c＝1.318 g/cm³, F(000)＝688, R₁＝0.0520, wR₂＝0.1108, S＝0.994.     

刺乌头碱氢溴酸盐的合成及晶体结构

报道了以双溴代烷烃和刺乌头碱合成刺乌头碱氢溴酸盐的方法. 用元素分析、红外光谱、高分辨质谱和核磁共振进行了表征. 并用X射线单晶衍射确定了标题化合物的绝对构型. 晶体结构表明, 该化合物通过分子间氢键形成了网状类似超分子结构. 晶体属于单斜晶系, P2₁空间群, 晶胞参数: a＝1.0619(2) nm, b＝1.2196(3) nm, c＝1.2282(2) nm, β＝90.87(1)°, V＝1.59037(54) nm³, Z＝2, D_m＝1.428 g/cm^－3, F(000)＝720.0, µ＝1.349 mm^－1. 环 A, B, C, D, E和F分别呈船式、椅式、信封式、船式、船式和信封式. 其绝对构型被确定为1S,4S,5S,7S,8S,9S,10S,11S,13R,14S,16S,17R.     

芳醛-N-(1-苯基-1H-四唑-5-巯基)乙酰腙的微波合成及其晶体结构

在微波辐射下快速、高产率地合成了一系列含有四唑环的酰腙类化合物, 并对其进行了元素分析、红外以及核磁共振氢谱和碳谱表征. 对化合物4a的无色晶体进行了X射线晶体衍射. 结果表明, 该晶体属三斜晶系, 空间群P-1, V＝0.80070(38) nm³, Z＝2, D_c＝1.404 g•cm^－3, a＝0.7382(1) nm, b＝0.9992(2) nm, c＝1.1535(2) nm, α＝81.41(2)°, β＝85.72(2)°, γ＝72.21(2)°, 分子结构呈反式构型, 通过分子间氢键组装成二聚体. 生物活性测试发现部分化合物具有抗菌活性.     

OH自由基的高精度量子化学研究

采用内收缩MRCI方法(Internally Contracted Multiconfiguration-Reference Configuration Interaction)研究了OH自由基, 计算得到其基态稳定构型的键长是0.09708 nm, 对应的实验值是0.096966 nm, 第一激发态的键长是0.10137 nm,实验值是0.10121 nm. 同时得到势能曲线PECs (Potential Energy Curve), 再分别由Murrell-Sorbie势能函数拟合计算和POLFIT程序计算得到OH自由基在基态X²Π和第一激发态A²Σ⁺时的光谱数据：平衡振动频率ω_e, 非谐性常数ω_eχ_e以及高阶修正ω_eY_e, 平衡转动常数B_e, 振转耦合系数α_e, 解离能D₀和垂直跃迁能量ν₀₀. 这些理论计算结果与最新的实验值非常吻合, 精确度比前人也有很大提高. 其中我们计算得到基态OH(X²Π)的解离能D₀＝35568.86 cm^－1, 第一激发态OH (A²Σ⁺)的解离能D₀＝18953.93 cm^－1, 从第一激发态A²Σ⁺ (ν＝0)到基态X²Π (v＝0)的垂直跃迁能ν₀₀＝32496.42 cm^－1.     

Ab initio Calculation of Intermolecular Dispersion Energy and Induction Energy of Nitramide Dimer

The dispersion energies, induction energies and their exchange counterparts (exchange-dispersion and exchange-induction energies) between two interacting nitramide molecules at several separations are derived based upon symmetry-adapted perturbation theory (SAPT). The results show that (1) the effect of intramonomer electron correlation on dispersion energies and induction energies for nitramide dimer system is remarkable especially in the region near the van der Waals minimum distance (0.42 nm). (2) At smaller separations the dispersion energies and the induction energies are largely quenched by their exchange counterparts, and this case in induction interaction is much more remarkable than in dispersion interaction. (3) Since at shorter distances there exists the strong short-range interaction due to electron transfer which quickly decays and even disappears at larger separations, the two different R-dependency formulae of induction energies were found: one is ca. R^-12.7 at short distances, and the other ca. R^-7.0 at large separations. The latter R-dependency is similar to that (ca.R^-7.2) of dispersion. (4) In the case of strong polar interaction existing in nitramide dimer, the “true“ induction correlation terms of higher order than ^1Eind^(22) may be important.     

PdYH分子的结构与势能函数

用密度泛函理论的B3LYP方法, 对钯和钇原子采用SDD收缩价基函数, 氢原子采用6-311＋＋G**全电子基函数, 对PdY和PdYH体系的结构进行优化. 计算表明: PdY分子的几何构型为C_∞v, 其基态为X²Σ^＋态, 键长R＝0.24168 nm, 离解能为D_e＝2.8261 eV, 谐振频率ω_e＝254.0656 cm^－1, 并拟合得到Murrell-Sorbie势能函数; PdYH分子最稳态为C_s构型, 电子组态为¹A', 平衡核间距R_PdY＝0.24281 nm, R_YH＝0.19824 nm, 键角∠PdYH＝116.7157°, 离解能D_e＝5.6146 eV, 基态简正振动频率: 对称伸缩振动频率ν₁ (a')＝348.2909 cm^－1, 弯曲振动频率ν₂ (a')＝243.3382 cm^－1, 反对称伸缩振动频率ν₃ (a')＝1442.2695 cm^－1. 由微观过程的可逆性原理分析了分子的可能离解极限. 并用多体项展式理论方法分别导出基态PdY和PdYH分子的势能函数, 其等值势能面图准确地再现了PdY和PdYH分子的结构特征和离解能, 由此讨论了Pd＋Y＋H分子反应的势能面静态特征.     

Cs(ATZ)的制备、晶体结构与热力学性质

以5-氨基四唑(ATZ)和氢氧化铯溶液为原料, 制备了配合物Cs(ATZ)并培养出单晶, 结构由X-ray单晶衍射测定. 晶体属正交晶系, 空间群Pnma, 晶体学参数: a＝0.8114(4) nm, b＝0.6907(4) nm, c＝0.9122(5) nm, V＝0.5113(5) nm³, D_c＝2.819 g/cm³, Z＝4, F(000)＝392, m＝7.112 mm^－1, R＝0.0485. 其中Cs^＋与9个氮原子配位, 分子间通过氢键、金属离子与N原子的桥连接及分子间作用力, 形成三维结构, 增加了晶体结构的稳定性. 同时, 用红外、拉曼光谱对配合物进行了表征. 根据测得的ATZ及Cs(ATZ)在氢氧化铯溶液中的反应焓和溶解焓, 算得配合物Cs(ATZ)标准摩尔生成焓为 (－430.56±0.43) kJ•mol^－1.     

Analysis of coupled cluster methods. II. What is the best way to account for triple excitations in coupled cluster theory?

Summary Various coupled cluster (CC) and quadratic CI (QCI) methods are compared in terms of sixth, seventh, eighth, and infinite order Møller-Plesset (MPn, n=6, 7, 8, ) perturbation theory. By partitioning the MPn correlation energy into contributions resulting from combinations of single (S), double (D), triple (T), quadruple (Q), pentuple (P), hextuple (H), etc. excitations, it has been determined how many and which of these contributions are covered by CCSD, QCISD, CCSD(T), QCISD(T), CCSD(TQ), QCISD(TQ), and CCSDT. The analysis shows that QCISD is inferior to CCSD because of three reasons: a) With regard to the total number of energy contributions QCI rapidly falls behind CC for largen. b) Part of the contributions resulting from T, P, and higher odd excitations are delayed by one order of perturbation theory. c) Another part of the T, P, etc. contributions is missing altogether. The consequence of reason a) is that QCISD(T) covers less infinite order effects than CCSD does, and QCISD(TQ) less than CCSD(T), which means that the higher investment on the QCI side (QCISD(T) :O(M ⁷), CCSD :O(M ⁶), QCISD(TQ) :O(M ⁸), CCSD(T) :O(M ⁷),M: number of basis functions) does not compensate for its basic deficiencies. Another deficiency of QCISD(T) is that it does not include a sufficiently large number of TT coupling terms to prevent an exaggeration of T effects in those cases where T correlation effects are important. The best T method in terms of costs and efficiency should be CCSD(T).     

Intermolecular Interactions in Weak Donor–Acceptor Complexes from Symmetry‐Adapted Perturbation and Coupled‐Cluster Theory: Tetracyanoethylene–Benzene and Tetracyanoethylene–p‐Xylene

The interactions in the complexes of tetracyanothylene (TCNE) with benzene and p‐xylene, often classified as weak electron donor–acceptor (EDA) complexes, are investigated by a range of quantum chemical methods including intermolecular perturbation theory at the DFT‐SAPT (symmetry‐adapted perturbation theory combined with density functional theory) level and explicitly correlated coupled‐cluster theory at the CCSD(T)‐F12 level. The DFT‐SAPT interaction energies for TCNE–benzene and TCNE–p‐xylene are estimated to be ?35.7 and ?44.9 kJ mol^?1, respectively, at the complete basis set limit. The best estimates for the CCSD(T) interaction energy are ?37.5 and ?46.0 kJ mol^?1, respectively. It is shown that the second‐order dispersion term provides the most important attractive contribution to the interaction energy, followed by the first‐order electrostatic term. The sum of second‐ and higher‐order induction and exchange–induction energies is found to provide nearly 40 % of the total interaction energy. After addition of vibrational, rigid‐rotor, and translational contributions, the computed internal energy changes on complex formation approach results from gas‐phase spectrophotometry at elevated temperatures within experimental uncertainties, while the corresponding entropy changes differ substantially.     

Characterization of the potential energy surfaces of two small but challenging noncovalent dimers: (P2)2 and (PCCP)2

This work characterizes eight stationary points of the P₂ dimer and six stationary points of the PCCP dimer, including a newly identified minimum on both potential energy surfaces. Full geometry optimizations and corresponding harmonic vibrational frequencies were computed with the second‐order Møller–Plesset (MP2) electronic structure method and six different basis sets: aug‐cc‐pVXZ, aug‐cc‐pV(X+d)Z, and aug‐cc‐pCVXZ where X = T, Q. A new L‐shaped structure with C₂ symmetry is the only minimum for the P₂ dimer at the MP2 level of theory with these basis sets. The previously reported parallel‐slipped structure with C_2h symmetry and a newly identified cross configuration with D₂ symmetry are the only minima for the PCCP dimer. Single point energies were also computed using the canonical MP2 and CCSD(T) methods as well as the explicitly correlated MP2‐F12 and CCSD(T)‐F12 methods and the aug‐cc‐pVXZ (X = D, T, Q, 5) basis sets. The energetics obtained with the explicitly correlated methods were very similar to the canonical results for the larger basis sets. Extrapolations were performed to estimate the complete basis set (CBS) limit MP2 and CCSD(T) binding energies. MP2 and MP2‐F12 significantly overbind the P₂ and PCCP dimers relative to the CCSD(T) and CCSD(T)‐F12 binding energies by as much as 1.5 kcal mol^?1 for the former and 5.0 kcal mol^?1 for the latter at the CBS limit. The dominant attractive component of the interaction energy for each dimer configuration was dispersion according to several symmetry‐adapted perturbation theory analyses. © 2014 Wiley Periodicals, Inc.     

Intermolecular potential energy surface for CS2 dimer

A new four‐dimensional intermolecular potential energy surface for CS₂ dimer is obtained by ab initio calculation of the interaction energies for a range of configurations and center‐of‐mass separation distances for the first time. The calculations were performed using the supermolecular approach at the Møller–Plesset second‐order perturbation (MP2) level of theory with the augmented correlation consistent basis sets (aug‐cc‐pVxZ, x = D, T) and corrected for the basis‐set superposition error using the full counterpoise correction method. A two‐point extrapolation method was used to extrapolate the calculated energy points to the complete basis set limit. The effect of using the higher levels of theory, quadratic configuration interaction containing single, double, and perturbative triple excitations QCISD(T) and coupled cluster singles, doubles and perturbative triples excitations CCSD(T), on the shape of potential energy surface was investigated. It is shown that the MP2 level of theory apparently performs extremely poorly for describing the intermolecular potential energy surface, overestimating the total energy by a factor of nearly 1.73 in comparison with the QCISD(T) and CCSD(T) values. The value of isotropic dipole–dipole dispersion coefficient (C₆) of CS₂ fluid was obtained from the extrapolated MP2 potential energy surface. The MP2 extrapolated energy points were fitted to well‐known analytical potential functions using two different methods to represent the potential energy surface analytically. The most stable configuration of the dimer was determined at R = 6.23 au, α = 90°, β = 90°, and γ = 90°, with a well depth of 3.980 kcal mol^?1 at the MP2 level of theory. Finally, the calculated second virial coefficients were compared with experimental values to test the quality of the presented potential energy surface. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011.