相转移催化条件下N-苯甲酰基-N'-芳基硒脲类化合物的合成及其超分子晶体结构

以PEG-400为固液相转移催化剂,通过苯甲酰氯与硒氰酸钾反应合成了中间体苯甲酰基异硒氰酸酯,该中间体不需分离,直接与芳胺反应,得到N-苯甲酰基-N'-芳基硒脲(2a～2p),这些化合物用1HNMR,IR及元素分析进行了表征,并用X射线单晶衍射确定了化合物2k的单晶结构.晶体结构表明,该化合物通过分子间氢键组装成了沿a轴无限延伸的一维链状超分子结构.晶体属于单斜晶系,P2(1)/c空间群,晶胞参数:a=1.1073(1)nm,b=0.5745(1)nm,c=2.4356(5)nm,β=92.10(1)°,V=1.5483(4)nm3,Z=4,μ=2.428.     

Liquid crystalline polymers: 14. Synthesis and thermal behaviour of some polyethers containing azo-mesogens

The paper presents a study on the relationship between the structure of macromolecular chain and its capacity to generate a mesophase, when mesogens with an azobenzene structure are implied. The polymers have been synthesized by phase transfer catalysis starting from 1,9-dichlorononane and different bisphenols: diphenyl-4,4^′-bis[(azo-4-)phenol], 4,4^′-dihydroxyazobenzene, 4,4^′-dihydroxydiphenyl, bisphenol A and 4,4^′-dihydroxybenzophenone. The polymers have been characterized by ¹H-NMR spectroscopy, DSC calorimetry, optical microscopy in polarized light and thermogravimetrical analysis. Theoretical conformational studies, using molecular simulations have also been performed. Due to their particular geometry, bis-(azobenzene) units are better mesogenic groups as compared with the azobenzene ones. The highly aromatic structure makes impossible the samples isotropisation, as the degradation processes starting advance. For these polymers, under UV irradiation, due to the presence of two azo groups in each mesogen unit, strong conformational modifications are expected. The replacement of the bis-(azobenzene) moieties with azobenzene ones reduces the transition temperatures, making possible the samples isotropisation.     

相转移催化下醇类的选择性电氧化

在选择性氧化的研究中,Cr(Ⅵ)类选择性氧化剂都存在着需特殊制备、配体和溶剂昂贵等缺点。同时,相转移催化技术的使用,也使许多氧化剂有了较好的选择性,但对环境污染严重。间接电氧化虽没有用量大、污染严重的缺点,但没有选择性。为此,我们使用间接电氧化和相转移催化氧化联用的方法,克服了上述缺点。并用Cr(Ⅵ)/Cr(Ⅲ)为间接氧化还原体系对醇类的选择性氧化进行了探讨。结果发现,本实验条件下,苄醇类会选择性地氧化成相应的羰基化合物,且产率高,而非苄醇类的醇则达不到此目的。     

Phase Transfer Catalysis in Polycondensation Processes: XVIII. Thermal properties and molecular simulation of some polyethers containing oxetane rings in the main chain

A study was made of the influence of the chemical structure of the chains on the thermal stability of a series of copolyethers obtained from 3,3-bis(chloromethyl)oxetane and various bisphenols: 4,4'-dihydroxyazobenzene, 4,4'-dihydroxydiphenyl, 4,4'-thiodiphenol, 1,1-bis(4-hydroxy-phenyl)ethane and 4,4'-dihydroxydiphenylsulfone. For a better correlation between chemical structure and thermal stability, molecular simulations were performed, using the HYPERCHEM (version 4.5) program. The lowest thermal stability was exhibited by the polymers that contain azobenzene units. The best thermal stability was that of the polyethers containing thiodiphenyl and 1,1-bis(phenyl)ethane units.This revised version was published online in November 2005 with corrections to the Cover Date.     

相转移催化下肟类的选择性间接电氧化研究

以Ｃｅ＾４＋／Ｃｅ＾３＋为间接电氧化还原体系，在相转移催化剂ＰｈＣＨ２Ｎ（Ｃ２Ｈ５）３Ｃｌ存在下，对肟类化合物进行选择性间接电氧化。结果表明，在室温条件下，电解２ｈ，肟类能被选择性地氧化为相应的羰基化合物，收率７５－９５．６％。     

相转移催化法合成仲丁基膦酸酯

报道了用相转移催化法合成仲丁基膦酸双正己酯以及将其水解转化为相应单酯的方法。该法产品纯，收率高，具有工业应用价值。     

相转移催化法合成芳氧基乙酸芳酯及硫赶酸苯酯

用液-液相转移催化法合成了35个芳氧基乙酸芳酯,5个芳氧基硫赶乙酸苯酯,与经典方法相比,相转移催化法有产率较高,反应条件温和,操作简便等优点。     

Efficient and Convenient Synthesis Ultrasound and Solid-liquid Phase of Diethers from Furoin Under Transfer Catalysis Conditions

Compounds having an active hydroxy group, such as, acyloins can be easily alkylated by alkyl halides in the presence of a phase transfer catalyst （PTC）. The reaction is usually carried out in the presence of con-centrated aqueous sodium or potassium hydroxide and a phase transfer catalyst, such as, quaternary ammonium salts^[1-3] species, miscible which facilitate the interphase transfer of making reactions between reagents in two im-phases possible. The reaction involves a series of equilibrium and mass-transfer steps.     

Efficient and Convenient Synthesis of Diethers from Furoin Under Ultrasound and Solid-liquid Phase Transfer Catalysis Conditions

Introduction Compounds having an active hydroxy group, such as, acyloins can be easily alkylated by alkyl halides in the presence of a phase transfer catalyst (PTC). The reaction is usually carried out in the presence of concentrated aqueous sodium or potassium hydroxide and a phase transfer catalyst, such as, quaternary ammonium salts[1-3], which facilitate the interphase transfer of species, making reactions between reagents in two immiscible phases possible. The reaction involves a series of equilibrium and mass-transfer steps.     

相转移催化合成酯基取代酞菁铜及其光导性能

酞菁配合物的大π键共轭体系使其具有独特的物理化学性能．但酞菁的难溶性,限制了其进一步的研究和应用．Baker等首次制备了可溶性酞菁单分子膜,并将其应用到光电池中;随后,已有大量的相关研究报道．作为常见的可溶性酞菁衍生物,酯基取代酞菁由于含酯基的前体物质高温分解而不能采用直接缩合的方法,     

相转移催化条件下N-苯甲酰基-N'-芳基硒脲类化合物的合成及其超分子晶体结构

以PEG-400为固液相转移催化剂, 通过苯甲酰氯与硒氰酸钾反应合成了中间体苯甲酰基异硒氰酸酯, 该中间体不需分离, 直接与芳胺反应, 得到N-苯甲酰基-N'-芳基硒脲(2a～2p), 这些化合物用¹H NMR, IR及元素分析进行了表征, 并用X射线单晶衍射确定了化合物2k的单晶结构. 晶体结构表明, 该化合物通过分子间氢键组装成了沿a轴无限延伸的一维链状超分子结构. 晶体属于单斜晶系, P2(1)/c空间群, 晶胞参数: a＝1.1073(1) nm, b＝0.5745(1) nm, c＝2.4356(5) nm, β＝92.10(1)°, V＝1.5483(4) nm³, Z＝4, μ＝2.428.     

9-(4-溴丁基)-9H-咔唑的相转移催化合成、表征及室温磷光性能研究——推荐一个大学化学综合实验

推荐了一个大学化学综合实验9-(4-溴丁基)-9H-咔唑的相转移催化合成、表征及室温磷光性能研究。实验利用相转移催化合成9-(4-溴丁基)-9H-咔唑分子,采用核磁共振、高分辨质谱和红外光谱对其分子结构进行表征,并利用紫外-可见吸收光谱、稳态/瞬态荧光光谱和密度泛函(DFT)理论计算对其室温磷光性能进行研究。本综合实验涵盖了有机化学、分析化学、物理化学、仪器分析以及理论化学的知识点,建议纳入化学专业高年级综合实验课程。     

A Novel One‐Step Synthesis of Symmetrical Dialkyl Trithiocarbonates in the Presence of Phase‐Transfer Catalysis

Symmetrical trithiocarbonates were directly obtained, in moderate to excellent isolated yields, by the reaction of various primary, secondary, allylic and benzylic halides or alkyl tosylates with a suspension of granulated KOH and alumina in CS₂ under phase‐transfer catalysis. In this manner, cyclic trithiocarbonates such as 1,3‐dithiolane‐2‐thione can also be prepared without formation of any polymeric by‐products.     

On the Roles of Electron Transfer in Catalysis by Nanoclusters and Nanoparticles

Electron transfer plays a major role in chemical reactions and processes, and this is particularly true of catalysis by nanomaterials. The advent of metal nanoparticle (NP) catalysts, recently including atomically precise nanoclusters (NCs) as parts of nanocatalyst devices has brought increased control of the relationship between NP and NC structures and their catalytic functions. Consequently, the molecular definition of these new nanocatalysts has allowed a better understanding and management of various kinds of electron transfer involved in the catalytic processes. This Minireview brings a chemist‘s view of several major aspects of electron-transfer functions concerning NPs and NCs in catalytic processes. Particular focus concerns the role of NPs and NCs as electron reservoirs and light-induced antenna in catalytic processes from H₂ generation to more complex reactions and sustainable energy production.     

Novel Bis-(N-alkyl-N ,N-dimethyl-ammonium) Polyethyleneglycol Ether Salts as Phase Transfer Catalysts in the Condensation of l,4-Diacetyl-2,5-piperazinedione and Aldehydes

Phase transfer catalysis (PTC) has become one of the most extensively used techniques in organic synthesis. The key factor in such processes is the catalyst. There are mainly two kinds of phase transfer catalysts, one is the so called "crown ethers" including macrocyeles, open chain molecules with long chains, bearing heteroatoms at a proper distance, and can chelate inorganic     

酞菁-卟啉超分子的形成及光致电子转移过程

用吸收光谱的方法研究了溶液中四－（４’－Ｎ，Ｎ，Ｎ－三甲基）－苯氧基）酞菁季铵碘盐及它的锌络合物与四－（４’－磺酸基苯基）卟啉及它的锌络合物通过分子间自组装形成的新一类超分子排列的杂聚体，用Ｊｏｂ氏光度滴定的方法确定了它们的组成，为面对面的杂二聚体或三明治式的杂三聚体超分子排列，证实卟啉和酞菁的中心络合金属与溶剂分子之间的轴向配位是决定了卟啉，酞菁杂聚体的组成，发现在超分子体系中卟啉与酞菁能互相猝     

芳烃化合物结构参数与色谱保留值关系的探讨

在自制的十六烷基磷酸锡固定相、甲醇－水流动相的色谱体系中，建立了烷基取代苯、不同数目的甲基取代苯、稠环芳烃等溶质的色谱保留值与其分子结构参数（分子连接性指数、范德华体积）之间的回归方程，并用疏溶剂理论予以解释，同时探讨了结构参数与色谱热力学的关系。