α-乙炔基吡啶的合成

研究了α 乙炔基吡啶的合成方法,得出了炔醇化的最佳反应条件为:m〔Pd(PPh3)2Cl2〕/m(2 溴吡啶)=5×10-3,反应时间6h,反应温度60℃,炔醇化的产物转化率为93%。脱丙酮消去反应的最佳条件为:n(氢氧化钠)/n(反应物)=0 75,反应温度80℃,反应时间6h,产物转化率为86%,产物经红外、核磁共振和元素分析确证。

强酸环境中溴化-N-烷基炔醇吡啶对X70钢的缓蚀性能

为防止X70钢在强酸环境中的腐蚀行为,开发新的缓蚀剂成为迫切需求。以2-氯甲基吡啶、炔丙醇和溴代十四烷为原料,经炔化、季铵化得缓蚀剂溴化-N-烷基炔醇吡啶(NTHPB),其结构经核磁共振谱(^(1)H-NMR、^(13)C-NMR)、质谱(MS)和红外光谱(FTIR)证实。采用失重法、极化曲线法和交流阻抗法评价了NTHPB在5 mol·L^(-1) HCl中对X70钢的缓蚀性能,用扫描电镜、X-衍射仪、紫外光谱和接触角研究了NTHPB在X70钢表面的吸附行为。结果表明,NTHPB对X70钢的缓蚀性能非常优异,5×10^(-5 )mol·L^(-1)的NTHPB在60℃、5 mol·L^(-1) HCl中对X70钢的缓蚀率高达99.54%,且缓蚀率随NTHPB浓度的增加而增加,随温度的升高而降低。NTHPB在X70钢表面的吸附属于物理和化学混合吸附的自发放热过程,遵循Langmuir等温吸附规律。本研究为抗强酸、高性能缓蚀剂的开发设计指明了新的方向。

多功能化硅氢抑制剂在加成型硅橡胶中的应用

采用气相色谱仪、差示扫描热仪、无转子硫化仪等仪器,考察了烷氧基硅烷化炔属化合物P2-1和P2-2对小分子硅氢加成反应、乙烯基封端聚二甲基硅氧烷和含氢硅油混合物的硅氢化反应的抑制行为,以及对加成型液体硅橡胶性能的影响。结果表明,P2-1和P2-2与有机硅材料具有良好相容性、相对低的挥发性、优异的硅氢加成抑制性能。与甲基丁炔醇和乙炔基环己醇相比,P2-1和P2-2可以让硫化物的表面更平滑。

Highly selective catalysts for the hydrogenation of alkynols:A review

The semi-hydrogenation of alkynols to enols is a crucial process in the production of pharmaceuticals,agrochemicals,fragrances,and flavors that involves a complex set of parallel and consecutive isomerization and hydrogenation reactions and proceeds via several key intermediates.In view of the industrial importance of large-scale enol production through alkynol hydrogenation,various noble and non-noble metal(e.g.,Ni and Pd)-based catalysts promoting this transformation have been developed.This paper reviews the design of highly selective catalysts for the semi-hydrogenation of alkynols,focusing on the role of additives,second metals,catalyst supports,and reaction conditions and combining catalytic reaction kinetics with theoretical calculations to establish the reaction mechanism and the decisive factors for boosting selectivity.Finally,a strategy for designing highly efficient and selective catalysts based on the characteristics of aqueous-phase alkynol hydrogenation is proposed.

Synthesis of α-hydroxy ketones by copper（Ⅰ）-catalyzed hydration of propargylic alcohols: CO2 as a cocatalyst under atmospheric pressure

Inexpensive and efficient Cu(Ⅰ) catalysis is reported for the synthesis of α-hydroxy ketones from propargylic alcohols, CO2, and water via tandem carboxylative cyclization and nucleophilic addition reaction. Notably, hydration of propargylic alcohols can be carried out smoothly under atmospheric CO2 pressure, generating a series of α-hydroxy ketones efficiently and selectively. This strategy shows great potential for the preparation of valuable α-hydroxy ketones by using CO2 as a crucial cocatalyst under mild conditions.

Electrochemical Remediation of 17α-Ethinylestradiol

Technological development has led to the emergence of new substances with many different purposes generating a new profile of pollutants in waterways. Among these, endocrine disruptors, such as 17EE （17ct-ethinylestradiol）, are of great importance due to their wide application and harmful consequences to the environment, human health and animals. The inefficiency of most water treatment processes in withdrawing such substances poses a global concern for the development of effective and environmentally clean methods. The electrochemical remediation processes appear as a powerful and ＂green＂ alternative for waste removal of organic or inorganic pollutants from complex environments, such as geosphere and hydrosphere. The research focus in this field is mostly related to the optimization of electronic devices with higher （photo） catalytic efficiency, whereas the starting material remains based on metal and carbon conventional electrodes. In the present study, the anodic removal process of 17ct-ethinylestradiol at carbon cardboards was investigated in stationary and hydrodynamic conditions. The influence of pH and applied potential were evaluated, always taking into account the transposition of scale and environmental aspects. Thus, the principle of hormone removal showed to be strictly related to such parameters. It was observed that mild alkaline medium favors the anodic oxidation, whereas neutral and mild acid ones lead to higher adsorption at carbon surface. Also, when the applied potential was higher than 1.25 V, the electrochemical oxidation rate increased, and the adsorption was decreased. Furthermore, the removal efficiency of ! 7EE showed to be lower, the flow rate was higher.

Rhodium(Ⅲ)-catalyzed selective access to isoindolinones via formal [4+1] annulation of arylamides and propargyl alcohols

A mild and efficient oxidative synthesis of isoindolinones has been realized by Rh(III)‐catalyzed C?H activation of benzamides and[4+1]coupling with propargyl alcohols.This coupling system proceeds with broad substrate scope and mild conditions and provides a new approach to access the useful skeleton ofγ‐lactams with a stereogenic center.