甲烷与氯气取代反应实验装置的改进及反应条件的探究

针对甲烷与氯气取代反应实验的困难和不足,改进了实验装置,并就如何控制反应所需的光照、温度等条件进行了一些实验探究,指出了合理的实验方法.同时解释了实验过程中的2个特殊现象.     

密度泛函理论研究温度和取代基对4-亚芳基亚氨基-1,2,4-三唑-3(2H)-酮气相热分解的影响

采用密度泛函理论(DFT)方法, 在B3LYP/6-31＋＋G(d,p)水平上研究了4-亚芳基亚氨基-1,2,4-三唑-3(2H)-酮及其类似物的气相热分解反应. 从热力学性质、几何结构参数、自然电荷分布、温度效应等角度探讨不同取代基对标题物热分解反应的影响. 结果表明: R (R＝H, CH2CH2CN)取代基对反应影响很小; 而苯环上Y (Y＝MeO, Me, H, Cl和NO2)取代基对活化自由能(ΔG≠)、键长(ΔR≠)、键角(Δα≠)和自然电荷(Δq≠)变化的影响与Hammet常数(σ)呈现线性关系ΔP≠＝ρσ＋C (P＝G, R, α和q, r＞0.95). 给电子基团使得相应的活化自由能降低, 键长变短, 键角变大, 自然电荷增加; 吸电子反之.     

离去基团、非离去基团及中间体性质对取代苯甲酸苯酯氨解反应的影响

X-取代苯甲酸Y-取代苯基酯(X-C6H4COOC6H4-Y)的氨解反应是一个亲核加成-消除过程.为定量评价Um等对非离去基团(X-C6H4-)、离去基团(Y-C6H4O-)及中间体(T±)的性质对氨解反应速率(kN)影响的研究结果,分别用取代基x的Hammett常数σX、Y-C6H4OH的pKa和取代基X、Y的极化效应指数PEI表征上述结构因素,并用其对logkN建立多元线性回归模型,得到了良好的相关结果.进一步分析得出,Y-C6H4OH的pKa对logkN的影响最大(贡献率为90.46%),而取代基X的Hammett常数σX影响最小.     

Synthesis,Crystal Structure and Herbicidal Activity of N-（4-Methylbenzyl）-4-（3-fluorophenyl）-4-piperidinol Hydrochloride

A novel compound N-（4-methylbenzyl）-4-（3-fluorophenyl）-4-piperidinol hydrochloride has been synthesized and its structure （C19H23ClFNO, Mr = 335.83） was characterized by elemental analysis, IR, ^1H NMR, MS and single-crystal X-ray diffraction analyses. The crystal belongs to the triclinic system, space group P1 with a = 7.2163（6）, b = 10.7905（9）, c = 12.2651（10） A, α = 109.576（2）,β = 98.407（2）,γ= 95.956（2）°, V= 878.14（13）A3, Z = 2, Dc = 1.270 g/cm^3,μ = 0.231 mm^-1, F（000） = 356, S = 1.100, the final R = 0.0525 and wR = 0.1425 for 3206 unique reflections （Rint = 0.0140） with 2736 observed ones （I 〉 2σ（I））. The piperidine ring exhibits a chair conformation. The dihedral angle made by the methyl- and fluoro-substituted benzene rings is 66.84（7）°. There are some intra- and intermolecular hydrogen bonding interactions among the molecules, which stabilize the whole crystal structure. The preliminary biological activity tests indicate good herbicidal activity for the title compound, in particular against the roots of some tested plants （such as Brassica campestris L. and Echinochloa crusgallis L.）.     

Synthesis of novel 3,5-disubstituted-dihydroisoxazoles from methyl undec-10-enoate and isoxazoles,triazole and tetrazolo-triazole from methyl undec-10-ynoate

The efficient cycloaddition reactions were carried out to afford the novel 3,5-disubstituted-dihydroisoxazoles from methyl undec-10-enoate and isoxazoles, triazole and tetrazolo-triazole from methyl undec-10-ynoate. The reactions occurred under relatively mild conditions and afforded the desired products in good yields.     

The simple synthesis of quinazoline-2,4-dione derivatives using Boc strategy

Quinazolinediones are particularly attractive pharmacophores because of their wide range of bioactivities. A convenient synthetic pathway to three-substituted quinazoline-2,4-dione derivatives was developed from substituted anthranilamide via carbonylation with Boc anhydride and then cyclization in the presence of the base sodium methoxide. Good to excellent yields have been achieved.     

Regio- and stereo-selective synthesis of multi-substituted 3-pyrrolines

A regio-and stereo-selective synthesis of multi-substituted 3-pyrrolines has been developed.The multi-substituted 3-pyrrolines were synthesized in good yields by 1,3-dipolar cycloaddition of methyl 2-(phenylselanyl)acrylate with azomethine ylides,followed by N-acylation and oxidation-elimination of phenylseleno group.     

α-巯基-β-取代苯基丙烯酸的合成及其对昆虫酚氧化酶的抑制活性

取代苯甲醛与罗丹宁经缩合反应,再经碱性水解,酸化等步骤合成了7种新的α-巯基-β-取代苯基丙烯酸,其结构通过1H NMR, IR和元素分析表征.生物活性实验表明,部分目标化合物对菜青虫酚氧化酶的活力有良好的抑制作用.     

掺杂丙烯酸酯单体合成及泡沫制备技术

通过丙烯酸、2-甲基丙烯酸、巴豆酸与五氯苯酚的酯化反应实现了3种丙烯酸酯单体的掺杂改性合成,采用核磁共振和质谱测试技术对掺杂丙烯酸酯单体进行了表征。利用掺杂改性后的丙烯酸单体与季戊四醇四丙烯酸酯之间的共聚反应,结合超临界萃取技术,制备出理论密度为50 mg·cm-3、掺杂氯元素质量百分数平均值最高约为15%的掺杂丙烯酸酯聚合物泡沫。通过测定聚合物凝胶速率,初步探讨了掺杂丙烯酸酯单体与多元丙烯酸酯单体的共聚合反应机理。     

ATRP法合成两亲的含氟柱状刷PBIEM-g-(PAA-b-PFA)

以聚甲基丙烯酸[2-(2-溴异丁酰氧)]乙酯(PBIEM)为大分子引发剂,采用接出(grafting from)原子转移自由基聚合(ATRP)技术合成了以聚丙烯酸叔丁酯-b-聚含氟丙烯酸酯为侧链的柱状分子刷PBIEM-g-(PtBA-b-PFA).通过GPC,1H-NMR和FTIR对PBIEM-g-(PtBA-b-PFA)组成和结构进行了表征,证实ATRP过程中没有发生分子间或分子内偶合反应,制备得到可控性好的含氟嵌段共聚物刷.利用大分子链中叔丁酯基团的水解反应生成两亲的含氟柱状刷PBIEM-g-(PAA-b-PFA),原子力显微镜可直接观察到PBIEM-g-(PAA-b-PFA)特征的核壳型柱状结构,得到聚合物刷的整体长度为ln=54~72 nm.