Visible-light-induced,autopromoted nickel-catalyzed three-component arylsulfonation of 1,3-enynes and mechanistic insights

Science China Chemistry - A light-induced, nickel-catalyzed three-component arylsulfonation of 1,3-enynes in the absence of photocatalyst is reported. This methodology exhibited mild conditions,...     

绿色氧化法制备联苯类化合物的研究性实验设计与实践*

以苯甲醛和丙酮为原料,利用Robinson增环反应先制备3-甲基-5-苯基环己-2-烯-1-酮,再引导学生设计并研究了水相绿色氧化3-甲基-5-苯基环己-2-烯-1-酮合成联苯类化合物3-乙氧基-5-甲基-1,1′-联苯的影响因素,利用核磁共振确定了产物结构。该研究性实验教学以绿色化学为中心,结合了2步连续反应,产物易提纯且产率高,并开展了开放式大型分析仪器教学和测试,对学生有机合成实验能力和科学研究能力的培养具有很好的教学效果。     

掺Fe3+A-TiO2粉末的制备及其可见光催化降解碱性品红

以硫酸钛为原料用水热法制备了掺Fe3+TiO2粉末,用SEM测定了样品的形貌和晶型,研究了以自制的掺Fe3+ A-TiO2对碱性品红溶液的光催化降解作用.结果表明:所制备的TiO2为锐铁矿型TiO2(A-TiO2).可见光照射下,用自制的掺Fe3+A-TiO2降解碱性品红溶液的最佳条件是:2mg·L-1的碱性品红溶液中...     

有机化学创新设计性实验“甲基化反应”的改进*

结合科研成果及实验教学经验,对有机化学实验中传统的甲基化反应实验进行改进。教材中涉及的传统甲基化试剂具有毒性大等缺点,不利于实验教学的实施。因此,提出使用三氟乙酸甲酯取代传统甲基化试剂,应用于本科有机化学实验教学中,加强学生对甲基化反应理论知识的理解。本实验结合新颖的科研内容,引入科研实验的设计思路,不仅有利于学生更好地掌握理论知识,而且有利于激发学生对科学研究的兴趣,提高学生的综合素养。     

化学专业学生线上学习平台和学习效果评价研究*

从学生视角简要介绍了钉钉、腾讯会议、腾讯课堂、中国大学MOOC、QQ群等多个在线学习平台的特点和使用方法。基于2020年第一学期高校开展线上教学的实践,通过对化学及相关专业本科生进行问卷调查,发现由于缺少纸质教材、师生互动不便、网络平稳性差、学生听课时自控力不好等原因,学生对居家线上课堂听讲情况、学习态度等的自我满意程度较在校学习时差,一定程度上影响了学生线上专业学习的效果。基于调查结果,从专业教师和学生2个方面就提升线上教学效果提出了建议。     

Facile synthesis of axially chiral styrene-type carboxylic acids via palladium-catalyzed asymmetric C–H activation

A novel method by a one-step introduction of axial chirality and sterically hindered group has been developed for facile synthesis of axially chiral styrene-type carboxylic acids. With the palladium-catalyzed C–H arylation and olefination of readily available cinnamic acid established, this transformation demonstrated excellent yield, excellent stereocontrol (up to 99% yield and 99% ee), and broad substrate scope under mild conditions. The axially chiral styrene-type carboxylic acids produced have been successfully applied to Cp*Co^III-catalyzed asymmetric C–H activation reactions, indicating their potential as chiral ligands or catalysts in asymmetric synthesis.

Palladium-catalyzed asymmetric C–H functionalization to yield axially chiral styrene-type carboxylic acids is described, in which axial chirality and sterically hindered group were incorporated in one-step.     

Self-Consistent Sources Extensions of Modified Differential-Difference KP Equation

In this paper, we investigate a modified differential-difference KP equation which is shown to have a continuum limit into the mKP equation. It is also shown that the solution of the modified differential-difference KP equation is related to the solution of the differential-difference KP equation through a Miura transformation. We first present the Grammian solution to the modified differential-difference KP equation, and then produce a coupled modified differential-difference KP system by applying the source generation procedure. The explicit N-soliton solution of the resulting coupled modified differential-difference system is expressed in compact forms by using the Grammian determinant and Casorati determinant. We also construct and solve another form of the self-consistent sources extension of the modified differential-difference KP equation, which constitutes a Bäcklund transformation for the differential-difference KP equation with self-consistent sources.