基于天然氨基酸的双环手性季铵盐相转移催化剂的合成及催化性能研究

以L－脯氨酸及L－羟基脯氨酸为原料合成了4个新型手性季铵盐磁相转移催化 剂，并用于催化不对称查耳酮环氧化反应，高产率得到相应环氧化合物，ee最高达 9％。     

Conductivity Studies of Dilute Aqueous Solutions of Oxalic Acid and Neutral Oxalates of Sodium, Potassium, Cesium, and Ammonium from 5 to 35°C

Conductivity measurements of oxalic acid and neutral oxalates (disodium oxalate, dipotassium oxalate, dicesium, and diammonium oxalate) were performed on dilute aqueous solutions, c < 3 × 10^–3 mol-dm^–3, from 5 to 35°C. These data and those available from the literature were analyzed in terms of dissociation steps of oxalic acid, the Onsager conductivity equation for neutral oxalates, the Quint–Viallard conductivity equation for the acid, and the Debye–Hückel equation for activity coefficients, to give the limiting equivalent conductances of bioxalate anion ;(HC₂O₄ ^–) and oxalate anion (1/2C₂O₄ ^2–) and the corresponding dissociation constants K ₁ and K ₂.     

Theoretical study of reaction channels for the weakly bound complex systems created with HF,CO2, and various amines

This investigation conducted reaction channels of weakly bound complexes CO₂…HF, CO₂…HF…NH₃, CO₂…HF…NH₂CH₃, CO₂…HF…NH(CH₃)₂, and CO₂…HF…N(CH₃)₃ systems, using the Gaussian 98 package at the B3LYP/6‐311++G(3df,2pd) level. The syn‐fluoroformic acid or syn‐fluoroformic acid plus NH₃ or amine conformers are more stable than the related anti‐fluoroformic acid or anti‐fluoroformic acid plus NH₃ or amine conformers. However, the above‐mentioned weakly bound complexes are more stable than both the related syn‐ and anti‐type fluoroformic acid or acid plus NH₃ or amine conformers and their related decomposed into CO₂ + HF or CO₂ + NHR₃F (R?H, CH₃) combined molecular systems. Five reaction channels of the weakly bound complexes exist. Each channel includes weakly bound complexes and their related above‐mentioned systems. Moreover, each reaction channel contains two transition states. The transition state between the weakly bound complex and anti‐fluoroformic acid type structure (T₁₃) is significantly higher than that of internal rotation (T₂₃) between syn‐ and anti‐FCO₂H (or FCO₂H…NR₃) structures. However, the above‐mentioned T₁₃ can significantly decrease its energy by adding the third molecule NH₃ or NR₃ (R?H or CH₃). The more CH₃ that is substituted in NR₃ of the reaction channel, the lower the activation energy of the transition state in the system is affected. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005     

一步室温固相化学反应合成纳米氨基酸杂多电荷转移配合物(HPhe)3PMo12O40·2H2O

以Keggin结构的钼磷酸(H3PMo12O40·13H2O)与苯丙氨酸(Phe)为原料,利用一步固相化学反应于室温合成了纳米氨基酸杂多电荷转移配合物(HPhe)3PMo12O40·2H2O,采用元素分析,IR,XRD,TEM,UV和循环伏安法等手段对其进行了结构表征及性质研究.结果表明,标题化合物纳米粒子为均匀的球状,粒径约为30～40nm.该化合物中杂多阴离子部分仍保持Keggin结构,但在钼磷酸与苯丙氨酸之间发生了显著的电荷转移.     

Zur Kenntnis des Calciumbromats und - iodats,Kristallstruktur, röntgenographische,IR- und Raman-spektroskopische und thermoanalytische Untersuchungen

On Calcium Bromated and Iodates – Crystal Structure, X-Ray, IR and Raman Spectroscopical and Thermoanalytical Investigations The phase relationships (and both decomposition and disproportionation)of bromates and iodates of alkaline earth metals are studied by means of thermal analyses (DTA, DSC, TG) and (high-temperature) X-Ray, IR-, and (high-temperature) Raman spectroscopic measurements. The following compounds have been established: Ca(IO₃)₂ · 6 H₂O oF 216, the isotypic Ca(BrO₃)₂ · H₂O and Ca(IO₃)₂ · H₂O mP 48, Ca(IO₃)₂ I (Lautarit) mP 36, Ca(IO₃)₂ II and Ca(BrO₃)₂. The Crystal structure of Ca(IO₃)₂ · H₂O (brüggenite) (space group P2₁/c, Z = 4) has been determined by single crystal X-ray diffraction (MoKα). The final R value for 3888 reflections with I_o > 3σ₁ is 0.0487. The structures of bromates and iodates of alkaline earth metals known so far are discussed with respect to the energetic (mode frequencies) and geometric (bond lengths) distortion of the XO₃–ions as well as the strengths of H-bonds present in the respective hydrates.     

POLYMER-SUPPORTED LEWIS ACID CATALYSTS. Ⅵ. POLYSTYRENE-BONDED STANNIC CHLORIDE CATALYST

A polystyrene-bonded stannic chloride catalyst was synthesized by the method of lithium polystyryl combined with stannic chloride. This catalyst is a polymeric organometallic compound containing 0.25 mmol Sn (Ⅳ)/g catalyst. The catalyst showed sufficient stability and catalytic activity in organic reaction such as esterification, acetalation and ketal formation, and it could be reused many times without losing its catalytic activity.     

铑配合物催化甲醇羰基化反应的性能和机理

本文合成了２－丁酸甲酯吡啶与四羰基二氯二铑形成的螯合形配合物，并用Ｘ射线光电子能谱（ＸＰＳ），红外光谱（ＩＲ）及核磁共振（ＮＭＲ）研究确定了其配位结构特征，通过甲醇羰基化制备乙酸的反应揭示了其结构特征对催化剂活性及稳定性的影响，并提出了可能的反应机理。     

Molecular structure of potassium [N,N′-bis(salicylideneamino)nitroguanidonate-N,N′,-O,O′]nickel(ii), the product of condensation of (salicylideneamino)nitroguanidine with salicylaldehyde on a Ni2+ ion template

The crystal structure of the product of the condensation of (salicylideneamino)nitroguanidine with salicylaldehyde on a Ni²⁺ ion template, K[Ni(C₁₅H₁₀N₅O₄)] · DMF, has been studied. It was established that a planar Ni complex, consisting of isolated [NiL]^– anions and solvated [K⁺ · DMF] cations, is formed. The negative charge of the anion is localized mainly on the O atoms of the nitro group. The nitroguanidine fragment of the ligand occurs in the tautomeric form, which was not reported previously.Deceased in 1995Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2273–2277, September, 1996.     

L-谷氨酸、甘氨酸二元、三元体系中铽(Ⅲ)、钙(Ⅱ)的化学形态研究

在模拟生理条件下 (37℃ ,I=0 .1 5mol/ L Na Cl) ,用 p H电位法研究了铽 ( )、钙 ( )与 L-谷氨酸、甘氨酸二元、三元体系。确定了体系存在的物种 ,测定了体系中配合物的稳定常数。讨论了上述二元、三元体系中铽 ( )、钙 ( )的物种分布特点。     

25,26,27-三失碳-B-高-7-氧-6-酮-5α-胆甾-3α,24-二醇的合成

本文报道以3α-羟基-6-羰基-5α-胆烷酸甲酯(3)为原料经六步反应合成了油菜甾醇类似物25,26,27-三失碳-B-高-7-氧-6-酮-5α-胆甾-3α,24-二醇(9a).总产率14%.9a的促进植物生长作用是24-表油菜甾醇内酯的60%.