核心素养导向的基于思维导图的分析化学教学实践与探讨

运用"思维导图"这一教学策略,引导学生在学习过程中自发有效地对各知识点进行关联,构建完整的知识网络,进而改变学生单纯依靠"机械式"记忆的学习方法,锤炼其对知识点的凝练总结能力,培养学生的自主学习能力,实现基于核心素养培养观导向的以培养具有良好分析化学素养,具备竞争力和创新能力的高端人才培养目标。     

以核心素养为导向的聚合反应工程教学探讨——以“理想混合反应器的热稳定性”为例

在核心素养理念下,以聚合反应工程教材中的"理想混合反应器的热稳定性"小节教学设计为例,挖掘工程学科教学过程中蕴含的教育价值。通过对热稳定性原理的解析、探讨,以及对工业中热稳定性实例的分析,引导学生以工程科学思维去认识原理性概念;以探讨问题为驱动,进行探究式学习,培养学生工程问题意识和实践应用能力;在课程教学过程中落实大学生核心素养的培养和发展。     

运用图示思维提升化学素养的教学案例研究

通过教学实践,引导学生运用图示思维,学习化学学科核心知识,提高获取信息,分析问题和解决问题的能力,深入理解化学学科本质,有效提升化学素养。     

基于泛在学习的SPOC翻转实验教学探讨——以极化曲线的测定为例

以物理化学实验“碳钢在碳酸氢铵溶液中极化曲线的测定”实验为例,探索构建了基于泛在学习的SPOC的线上线下的翻转实验教学模式,其教学设计基本思路为：课前实验与理论相联系,培养学生基本技能;课中实验与专业相衔接,培养学生创新思维;课后实验与生产相融合,培养学生应用能力。实践表明,该教学模式不仅拓展了实验内容,而且极大地激发了学生的探究热情和创新思维,培养了学生的实际应用能力。     

核心素养下的聚合反应工程教学改革探索研究

聚合反应工程是一门工程实践性较强的课程,基于核心素养培养理念本门课程进行教学改革探索,将大学生核心素养的培养落实到课程教学中。以注重实践应用能力,强化工程意识培养为重点,培养学生融合各学科知识,形成完整的知识体系;与校外实践平台合作,提升学生的社会适应能力、实践应用能力和创新意识;深化课程教学评价机制改革。通过对核心素养与已有课程体系的融合,探究了核心素养下高校聚合反应工程课程的教学改革策略。     

关于CO2的两个性质实验的商榷

笔者学习了《化学教育》中有关用化学实验引导学生展开创新实验的文章，受益匪浅。利用探究性实验、演示实验、设计实验来培养学生创新精神和实践能力，已得到大家的共识，放在了应有的位置。但是，我们在利用实验培养学生创新思维时，不能一味追求新、奇，应注意当学生的思维进入误区时应给以点拨、纠正，不能置之不管，更不能连自己也不清楚。通过设计实验来培养学生创新思维时，不仅要注意实验的科学性、操作的示范性，还应注意图示的规范性，不能发生差错。     

近5年化学奥林匹克(初赛)试题的分析及建议

从化学核心素养出发，分析近5年化学奥林匹克（初赛）试题考查的学生知识水平、能力水平、素养水平，并针对培养中学生核心素养的教学实践提出建议。     

手持技术探究离子浓度对沉淀溶解平衡的影响——同离子效应和盐效应

基于手持技术探究同离子效应和盐效应对氢氧化镁沉淀溶解平衡的影响,通过将氢氧化镁水溶液的宏观变化与实验曲线相结合,进而推测微观的反应原理,最后再以可逆方程式等符号形式进行表征,从而提高学生的证据推理能力,实现“四重表征”思维模式的培养,为相关的教学提供素材。此外,针对实验过程中的“异常”现象,引导学生进行猜想假设、设计实验方案、开展实验探究等活动,发展学生的批判质疑思维与创新精神,提高解决冲突与灵活思维的能力,落实“科学探究”与“科学态度”等核心素养的培养。     

以课题研究为导向的重质油改质实验教学改革

以重质油改质实验为例,从课题研究方向的确立、方法的学习、手段的掌握、规律的研讨4个方面阐述了以课题研究为导向的实验教学改革。教学实践表明,以课题研究为导向的教学实验改革与探索,可以促进学生参与科研课题研究,使其在专业实验中尽快地运用科研思维来参与实验,有利于全方位培养学生的实践能力,强化科研能力方面的训练。     

新工科背景下环境化学实验教学的改革与实践

新工科背景下,实验教学改革旨在培养学生解决复杂工程问题及实践创新的能力。以环境化学实验为例,通过构建课题制的实验项目,并对其实施教学过程进行了改革与探索。实践表明,课题制实验可提升学生的自主参与学习和实践创新能力,促进学生理论知识、综合能力及综合素养的有机融合,是新工科理念在实验教学中的积极探索。     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.     

Synthesis of N-substituted carbazolones from α-iodo enaminones via Pd(0)-catalyzed intramolecular coupling under microwave irradiation

A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd₂(dba)₃-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Synthesis of substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular nitrilimine cycloaddition

Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.