双亲性希土-邻苯二甲酸正十四醇单酯-邻菲咯啉三元配合物的合成、表征、荧光特性及成膜性能

合成了双亲性的铕、铽-邻苯二甲酸正十四醇单酯-邻菲咯啉三元混配配合物，用红外光谱及差热-热重谱进行了表征。考察了发光性能。研究了它们在空气-水界面上的单分子膜行为，结果表明均具有良好的成膜行为。     

β－芳氧基丙酸衍生物的合成及生物活性

合成了β－芳氧基丙酸芳酯及β－芳氧基丙酰芳胺等１７种化合物，经ＩＲ、ＵＶ、１ＨＮＭＲ和元素分析确定了它们的结构，并对它们的生物活性进行了初步考察。     

β—芳氧基丙酸衍生物的合成及生物活性

合成了β－芳氧基丙酸芳酯及β－芳氧基丙酰芳胺等１７种化合物，经ＩＲ，ＵＶ，ＨＮＭＲ和元素分析确定了它们的结构，并对它们的生物活性进行了初步考察。     

三核苯甲酸铁配合物[Fe3O(OBZ)6(H2O)3](NO3)(acetone)5(OBZ-=苯甲酸根)的结构和磁性

合成了三核苯甲酸铁配合物［Ｆｅ３Ｏ（ＯＢＺ）６（Ｈ２Ｏ）３］（ＮＯ３）（ａｃｅｔｏｎｅ）５。测定了其晶体结构，其中三个铁形成等边三角形结构。配合物的变温磁化率表明，分子内三个铁之间有弱的反应磁性交换作用，Ｊ＝－３３．１８ｃｍ＾－１。分子之间则有更弱的反铁磁性交换作用，ＺＪ＾＇＝－１．１４ｃｍ＾－１。     

Dynamical intramolecular metal-to-metal ligand exchange of phosphine and thioether ligands in derivatives PtRu5(CO)16(mu6-C)

The complexes PtRu(5)(CO)(15)(PMe(2)Ph)(mu(6)-C) (2), PtRu(5)(CO)(14)(PMe(2)Ph)(2)(mu(6)-C) (3), PtRu(5)(CO)(15)(PMe(3))(mu(6)-C) (4), PtRu(5)(CO)(14)(PMe(3))(2)(mu(6)-C) (5), and PtRu(5)(CO)(15)(Me(2)S)(mu(6)-C) (6) were obtained from the reactions of PtRu(5)(CO)(16)(mu(6)-C) (1) with the appropriate ligand. As determined by NMR spectroscopy, all the new complexes exist in solution as a mixture of isomers. Compounds 2, 3, and 6 were characterized crystallographically. In all three compounds, the six metal atoms are arranged in an octahedral geometry, with a carbido carbon atom in the center. The PMe(2)Ph and Me(2)S ligands are coordinated to the Pt atom in 2 and 6, respectively. In 3, the two PMe(2)Ph ligands are coordinated to Ru atoms. In solution, all the new compounds undergo dynamical intramolecular isomerization by shifting the PMe(2)Ph or Me(2)S ligand back and forth between the Pt and Ru atoms. For compound 2, DeltaH++ = 15.1(3) kcal/mol, DeltaS++ = -7.7(9) cal/(mol.K), and DeltaG(298) = 17.4(6) kcal/mol for the transformation of the major isomer to the minor isomer; for compound 4, DeltaH++ = 14.0(1) kcal/mol, DeltaS++ = -10.7(4) cal/(mol.K), and DeltaG(298) = 17.2(2) kcal/mol for the transformation of the major isomer to the minor isomer; for compound 6, DeltaH++ = 18(1) kcal/mol, DeltaS++ = 21(5) cal/(mol.K) and DeltaG(298) = 12(2) kcal/mol. The shifts of the Me(2)S ligand in 6 are significantly more facile than the shifts for the phosphine ligand in compounds 2-5. This is attributed to a more stable ligand-bridged intermediate for the isomerizations of 6 than that for compounds 2-5. The intermediate for the isomerization of 6 involves a bridging Me(2)S ligand that can use two lone pairs of electrons for coordination to the metal atoms, whereas a tertiary phosphine ligand can use only one lone pair of electrons for bridging coordination.     

Pseudolarolides O and P,Two Novel Triterpene Dilactones from Pseudolarix kaempferi

Pseudolarolides O ( 1 ) and P ( 2 ), two novel triterpenoids with a cycloartane‐type framework, were isolated from the seeds of Pseudolarix kaempferi Gord. (Pinaceae). Their structures were elucidated as (16R,23S,25R)‐16,23‐epoxy‐3,4 : 9,10‐disecocycloartan‐1(10),9(11)‐diene‐3(4),26(23)‐diolide ( 1 ), and (9S,16R,23S,25R)‐1,9 : 16,23‐diepoxy‐8,9 : 9,10‐disecocycloartan‐1(29),5(6),10(19)‐triene‐3(4),26(23)‐diolide ( 2 ), respectively, on the basis of spectroscopic techniques and X‐ray‐diffraction studies.     

MINDO/3研究胞嘧啶异构体间异构化反应——Ⅰ. N1-氢-4-氨基-2-羰基胞嘧啶与4-亚氨基-2-羰基胞嘧啶异构反应

本文报导用半经验方法研究N_1-氢-4-氨基-2-羰基胞嘧啶与4-亚氨基-2-羰基胞嘧啶异构化反应。用MINDO/3能量梯度法优化了孤立体系的全部自由度, 计算结果表明氨型比亚氨型稳定, △E=33.85 kJ mol~(-1); 限定分子体系在同一平面, 用Powell法优化过渡态几何构型, 计算所得正反应活化势垒为168.87 kJ mol~(-1), 逆反应活化势垒为135.02 kJ mol~(-1)。从IRC途径分析了该异构化反应的物理实质。     

Continuous medium theory for nonequilibrium solvation: I. How to correctly evaluate solvation free energy of nonequilibrium

Considering the influences of electrostatic potential Phi upon the change of solute charge distribution deltarho and rho upon the change deltaPhi at the same time, a more reasonable integral formula of dG = (1/2) integral (V) (rhodeltaPhi + Phideltarho)dV is used to calculate the change of the electrostatic free energy in charging the solute-solvent system to a nonequilibrium state, instead of the one of dG = integral (V) PhideltarhodV used before. This modification improves the expressions of electrostatic free energy and solvation free energy, in which no quantity of the intermediate equilibrium state is explicitly involved. Detailed investigation reveals that the solvation free energy of nonequilibrium only contains the interaction energy between the field due to the solute charge in vacuum, and the dielectric polarization at the nonequilibrium state. The solvent reorganization energies of forward and backward electron transfer reactions have been redefined because the derivations lead to a remarkable feature that these quantities are direction-dependent, unlike the theoretical models developed before. The deductions are given in the electric field-displacement form. Relevant discussions on the reliability of theoretical models suggested in this work have also been presented.     

The rotation–vibration coupling equations for polyatomic molecules in internal coordinates

An exact vibration–rotation kinetic energy operator for polyatomic molecules has been obtained on the basis of Sutcliffe's method, in terms of curvilinear internal coordinates and rotational angular moment operators. This operator is derived from the kinetic energy operator in Cartesian coordinates by the successive transformations using the chain rule. This kinetic energy operator can be used not only for the system of any triatomic and tetraatomic molecules and common polyatomic molecules in chemistry, but also for the investigation of the collision problems between two molecules after some modifications. Finally, using this Hamiltonian, the rotation–vibration coupling equations of polyatomic molecules have been derived and discussed. © 1992 John Wiley & Sons, Inc.     

A new gas chromatographic stationary phase: Polysiloxane with β-cyclodextrin side chain for the separation of chiral and positional isomers

Summary A new stationary phase [bikis(2,6-di-O-pentyl-3-O-hex-6-enyl)-pentakis(2,6-di-O-pentyl-3-O-methyl)-β-CD-polysiloxane] was synthesized and successfully applied in GC for the separation of chiral and achiral isomers. It possesses high column efficiency and exhibits excellent separation ability for disubstituted benzenes. Some typical enantiomers and optical isomers are well separated. The separation behavior of this new phase is characterized and discussed.