浅谈中国化学会《有机化合物命名原则2017》的教学要点

比较了中国化学会《有机化合物命名原则2017》与1980版命名原则的不同,指出了新版的主要变化之处。通过举例,说明母体氢化物、特性基团的概念、含义及其在命名有机化合物时的重要意义。归纳出命名有机物时确定母体氢化物和主特性基团所依据原则和方法,梳理出命名有机化合物的一般步骤,并通过实例来说明2017版命名原则的实施方法。     

计算环烷烃沸点的新方法——基团键贡献法

根据分子中基团的特性和连接性，发展了一种直接根据分子结构信息计算环烷 烃沸点的新方法——基团键贡献法，该方法既考虑分子中基团的特性，又考虑基团 之间的连接性（化学键），具有基团贡献法和化学键贡献法的特点。对256种环烷 烃沸点的计算结果表明，计算值与实验值的一致性令人满意，平均误差0.71。     

常见有机化合物中英文命名的新教学法*

基于英文命名的新有机化合物命名规则于2017年颁布以来,掌握有机化合物的英文命名就变得更加重要。介绍了有机化合物中英文命名的一种新教学方法,含单种特性基团化合物可以分为烃和非烃2类,根据官能团编号的特点,按照链状和环状化合物分类。含多种特性基团化合物主要考虑基团作为母体基团的优先顺序,以及醛和羧酸及其衍生物为取代基时其碳原子是否作为主链和环母体部分,分别开展有机化合物中英文命名教学,便于教师教和方便学生学,在教学实践中深受师生欢迎。     

对《有机化合物命名原则2017》中有关“顺序”问题的思考

在仔细学习《有机化合物命名原则2017》的基础上,将新规定中与1980版相比的主要变化,从主体基团选择顺序、取代基列出顺序、主体结构编号顺序、取代基及主体基团位次编号插入的位置、立体化学中的"顺序规则"等几个方面进行归纳与总结,以简洁明了的方式为有机化学的学习与教学提供一份参考。     

甲基丙烯酸甲酯和联苯酯的基团转移共聚

甲基丙烯酸甲酯和联苯酯的基团转移共聚邹友思，林国良，姚青青，潘容华（厦门大学化学系，厦门，３６１００５）关键词基团转移共聚，竞聚率，甲基丙烯酸甲酯，甲基丙烯酸联苯酯前文［１］报道了基团转移嵌段共聚的结果，用混合投料的方法进行了基团转移无规共聚并研究了...     

环氧化天然橡胶中环氧基团分布情况的研究

通过在胶乳状态下原位生成过氧甲酸制备环氧化天然橡胶（ENR），采用傅里叶变换红外光谱（FRIR）对环氧化天然橡胶的结构进行表征，核磁共振谱仪（NMR）和差示扫描量热仪（DSC）对环氧基团的分布进行了研究，结果表明，过氧甲酸能迅速地渗透到橡胶粒子的内部，使环氧化基团分布在整个橡胶粒子上，环氧基团在ENR分子链上是无规分布...     

甲基丙烯酸酯和丙烯酸酯基团转移共聚的竞聚率

甲基丙烯酸酯和丙烯酸酯基团转移共聚的竞聚率邹友思郭金全戴李宗潘容华（厦门大学化工系，厦门，３６１００５）基团转移聚合是制备极性单体的嵌段或无规共聚物的有效方法。如用甲基丙烯酸甲酯（ＭＭＡ）和丙烯酸丁酯（ＢＡ）进行嵌段共聚，可制得热塑性弹性体［１...     

丙烯腈和甲基丙烯酸酯基团转移共聚的竞聚率

丙烯腈和甲基丙烯酸酯基团转移共聚的竞聚率邹友思，郭金全，兰涛，戴李宗，潘容华（厦门大学化工系，厦门，３６１００５）关键词基团转移共聚．竞聚率．丙烯腈．甲基丙烯酸酯近年来对基团转移共聚竞聚率的研究较活跃［１～３］，一般认为甲基丙烯酸酯和丙烯酸酯两类单体...     

甲基丙烯酸酯的基团转移嵌段共聚研究

甲基丙烯酸酯的基团转移嵌段共聚研究戴李宗邹友思陈良坦潘容华（厦门大学化学系厦门３６１００５）关键词基团转移聚合，甲基丙烯酸酯，嵌段共聚物，结构表征基团转移聚合［１］（ＧｒｏｕｐＴｒａｎｓｆｅｒＰｏｌｙｍｅｒｉｚａｔｉｏｎ，ＧＴＰ）具有活性聚合的特点...     

基团转移嵌段共聚规律研究

基团转移嵌段共聚规律研究夏海平，丁马太，陈萍，郭舰，刘昆棱（厦门大学化学系，３６１００５）基团转移聚合（ＧＴＰ）￣［１］是８０年代出现的新型聚合方法。常用的ＧＴＰ单体主要有三类：甲基丙烯酸酯类、丙烯酸酯类及丙烯腈。由于ＧＴＰ能使某些单体在室温下进行“...     

The computation of the representation matrices of the generators of the unitary group

A method is presented for the efficient computation of the representation matrices of the unitary group, U(n) in the Gelfand—Tsetlin basis (corresponding to the usual spin-symmetry adapted basis for an N electron CI). The present scheme is conceptually and computationally attractive in that it is formulated directly in terms of Weyl tableaux and also that it permits simultaneous basis vector generation and matrix element evaluation. In addition the basis vectors are ordered so that subsequent restriction to the three dimensional rotation group is facilitated. An illustrative example is also presented.Taken in part from a thesis submitted to the University of London in partial fulfilment of the requirements for the degree of PhD.     

Peracetylated cellulose: end group modification and structural analysis by means of <Superscript>1</Superscript>H-NMR spectroscopy

A homologous series of partially hydrolyzed celluloses (level-off-DP cellulose) with weight-average molecular weight (DP_w) < 150 were peracetylated and characterized by ¹H-NMR spectroscopy. The results demonstrate the utility of ¹H-NMR spectroscopy to assign the chemical shifts of all end groups of the peracetylated cellulose. On the one hand, the chemical shifts of all methine and methylene protons of the non-reducing terminal end group (TEG) as well as the - and -anomer of the reducing end group (REG) could be determined by two-dimensional NMR techniques (COSY-DQF) and by selective excitation of isolated proton signals (1D-TOCSY) of these end groups. On the other hand, the spectral resolution was high enough to determine the number-average molecular weight (DP_n) of peracetylated level-off-DP cellulose (LODP cellulose acetates) as shown in comparison with the data of gel permeation chromatography (GPC). This molecular weight determination of cellulose using end group analysis by means of ¹H-NMR spectroscopy was demonstrated for the first time. Furthermore, a specific modification of hydroxyls in end groups could be exemplified in case of 1-OH-deacetylation of the REG of peracetylated LODP cellulose.     

Synthesis of secondary α-perfluoroalkyl- and tertiary α,α-bis(perfluoroalkyl)-N-methylprolinols and their catalytic activities in the acyl transfer reaction

Various chiral α-perfluoroalkyl-N-methylprolinols were prepared and their organocatalytic activities in an acyl transfer reaction of 4-nitrophenyl 2-methoxyacetate with methanol-d₄ in chloroform-d were examined. As a result, α-trifluoromethyl-N-methylprolinol was a more effective acyl transfer catalyst than not only secondary α-perfluorobutyl- and n-butyl-N-methylprolinols but also tertiary α,α-bis(perfluorobutyl)-N-methylprolinol.     

Regioselective replacement of nitro groups in 2,4,6-trinitrotoluene under the action of alkanethiols. Synthesis of ortho-(alkylthio)-substituted nitrotoluenes and their oxidation to sulfoxides and sulfones

The reactions of 2,4,6-trinitrotoluene with alkanethiols in the presence of K₂CO₃ (the molar ratio of the reactants is 1 : 1 : 1) in dipolar aprotic solvents result in selective replacement of the ortho-nitro group to form 2-alkylthio-4,6-dinitrotoluenes, which can be oxidized to the corresponding sulfoxides or sulfones. The second ortho-nitro group can be replaced under the action of one more equivalent of alkanethiol on sulfides as exemplified in PhCH₂SH.     

Preparation and properties of biocompatible polymer-grafted silica nanoparticle

Grafting of biocompatible polymer onto the surface of silica nanoparticles was achieved by radical graft polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC), initiated by azo groups previously introduced onto the surface or by a system consisting of Mo(CO)₆ and trichloroacetyl groups on the silica surface. Both of these systems have the ability to initiate graft polymerization of MPC, resulting in the formation of poly(MPC)-grafted silica, but the percentage of poly(MPC) grafting for the latter initiating system was much higher than that of the former. The amount of moisture that could be adsorbed onto the silica surface was found to increase with increasing poly(MPC) grafting. This indicates that grafting of poly(MPC) onto the silica surface markedly increases the hydrophilic nature of the surface. The contact angle of water in composites prepared from poly(vinyl alcohol) and poly(MPC)-grafted silica was found to decrease with increasing poly(MPC)-grafted silica content. When poly(MPC)-grafted silica was added to water containing a small amount of chloroform, it was found to act as stabilizer for droplets of chloroform. In addition, according to tests by the Lee-White method, poly(MPC)-grafted silica shows non-thrombogenic characteristics.     

Effects of Salts of Varying Nature on the Energy Stability of the Structure of Aqueous Solutions

For cyclopentane used as a model hydrocarbon, solubility in water and aqueous solutions of various salts (chlorides, bromides, iodides, rhodanides, alkali metal acetates and sulfates, and calcium and zinc chlorides) at 20±1°C has been determined. Variations of the increment of the methylene group ( ) induced by salt additions to water, are calculated. When the salt is added to the solution, the increment increases drastically irrespective of the nature of the ions, thus stabilizing the structure of the solution. The increase, however, depends significantly on the nature of the salt, which is explained by different degrees of structuring of the aqueous solution caused by the ions of the salts.     

A study on free‐volume properties of styrene‐acrylic ester type copolymers

The positron annihilation lifetime measurements have been performed on a number of amorphous styrene–methyl acrylate copolymers and styrene–butyl methacrylate copolymers. The densities of copolymers were obtained with immersion method by using a capillary pycnometer and the average molecular weights were determined by gel chromatography. The lifetime τ₃ of ortho‐positronium (o‐Ps) pick‐off annihilation have been found to correlate with side group volume and polarity of macromolecular chains in the copolymers, and relative intensity I₃ is attributed mainly to the electron‐attracting groups trapping the spur electrons and positrons. The experimental results have been discussed on the basis of the structural variation of macromolecular chains. In addition, the PALS measurement as a function of time for polystyrene and several styrene–methyl acrylate copolymers has also been performed. The result shows that an electric field is built in polymers during extended positron annihilation spectroscopy measurement, and the field effect is a main factor which causes the decrease in I₃ with time. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2476–2485, 1999     

Rearrangement of allylic azide and phenylthio groups of 3′-azido- or 3′-phenylthio-4′,5′-didehydro-5′-deoxyarabinofuranosyluridines

The reversible intramolecular [3,3]-sigmatropic rearrangement between 1-(3-azido-3,5-dideoxy-β-d-threo-pent-4-enofuranosyl)uracil (3) and 1-(5-azido-3,5-dideoxy-β-d-glycero-pent-4-enofuranosyl)uracil (4) and irreversible radical rearrangement of 1-(3,5-dideoxy-3-phenylthio-β-d-threo-pent-4-enofuranosyl)uracil (5) and 1-[3,5-dideoxy-3-(4-tolyl)thio-β-d-threo-pent-4-enofuranosyl]uracil (7) into 1-(3,5-dideoxy-5-phenylthio-β-l-glycero-pent-4-enofuranosyl)uracil (6) and 1-[3,5-dideoxy-5-(4-tolyl)thio-β-l-glycero-pent-3-enofuranosyl]uracil (8) were attained at room temperature.     

ChemInform Abstract: First Principles Calculations of Electronic Structure and Magnetic Properties of Cr‐Based Magnetic Semiconductors Al1‐xCrxX (X: N,P, As,Sb).

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