基于真实设计思想的有机合成高分子的深度学习*——以“耐热合成高分子材料聚酰亚胺”为例

依据《普通高中化学课程标准(2017年版)》新增了官能团--酰胺基,融入深度学习的理念,选取嫦娥四号月球探测器上五星红旗的材质--聚酰亚胺作为学习对象,从聚集态结构和分子结构2个维度建立研究高分子的耐热性的认识角度,参考科技工作者研究耐热高分子的思维过程设计学习过程,在学习核心知识的同时发展学生自身的化学学科核心素养。     

“绿色化学”的项目式教学*——环氧乙烷制备工艺中的绿色化学

以“环氧乙烷制备工艺中的绿色化学”为项目式学习主题,以绿色化学概念学习、化学工艺中绿色化学的设计评价等为项目学习活动,探究绿色化学理念的教学设计。培养学生绿色化学意识,提升科学态度和社会责任的化学学科核心素养。     

核心素养视域下化学与生活深度融合的教学*——以“碳酸钠和碳酸氢钠的性质及应用”为例

当前“碳酸钠和碳酸氢钠”的教学中,注重2者性质的分析比较,缺少对2者在生活应用的关注和亲身实践,学生无法切身感受碳酸钠与碳酸氢钠的实用价值。在核心素养视域下,化学教学应注意与生活深度融合。通过课前设置项目式学习和实践;课中汇报实践成果、进行实验探究、解决真实情境问题,使化学与生活深度融合,帮助学生深刻理解“碳酸钠和碳酸氢钠的性质及应用”,发展学生的学科核心素养,落实教、学、评一致性的要求。     

化学学科核心素养为本的高三化学深度复习*——以沉淀滴定为例

以沉淀滴定为例阐述在高三教学中进行化学学科核心素养为本的高三化学深度复习。分析了教学背景和复习目标,详细呈现了教学过程,并对教学效果进行了检测和反思。素养为本的高三化学深度复习关键是:创设真实情境,激发学习欲望;解决真实的问题,发展高阶思维;教、学、评一体化,促进素养提升。     

促进核心素养发展的气体摩尔体积教学软件研究

在分析气体摩尔体积的教学目标、内容、现状以及所蕴含的化学学科素养的前提下,研发了指向深度学习、促进学生化学学科核心素养发展的课堂教学软件。通过该教学软件呈现可视化证据,解决气体摩尔体积教学中的挑战性问题并实现深度学习。     

化学学科核心素养在高中教材习题中的表现—以人教版教材为例

教材习题是落实新课标倡导的基于化学学科核心素养进行评价的重要载体。以化学学科核心素养的水平划分和学业质量水平为依据,分析人教版高中必修化学教材课后习题考查的核心素养及其水平。结果表明,2007年版和2019年版教材均注重全面考查核心素养和对基础性的考查,突出考查宏观辨识与微观探析素养,突出化学本质;但2019年版教材习题在数量上有所减少,加强了科学思维和科学实践的考查,合理拓展了核心素养考查的广度和深度。最后,依据习题特征获得相应的教学启示,以促进学生核心素养的发展。     

学科核心素养视域下高中化学教材的新变化及教学启示*——以“化学与可持续发展”为例

基于学科核心素养视角对新、旧人教版教材的“化学与可持续发展”主题进行比较分析,厘清教材内容的变化并充分挖掘教材修订对学生学科核心素养的培育价值,抽提素养发展功能,分析教学价值取向,为有效开展新课标理念下的化学教学提供参考。     

生活境脉促体验 实验创新助探究—指向核心素养发展的“铁及其化合物的应用”教学实践

有机融合学生生活中的经验与体验和化学学习中的认知与思维,可优化课堂进程,提高学习效率,让化学知识建构的过程同时成为化学学科核心素养发展提升的过程。在“铁及其化合物的应用”的教学中,以“笔·墨”为情境生成真实问题,在互动、探究、体验中整合物质性质,建构思维模型,并应用模型解决问题,发展科学探究、证据推理、模型认知等化学学科核心素养。     

基于真实问题情境的化学活动课设计*——以“氧化铁与酸的反应”为例

基于联系生活实际的真实问题情境,设计化学活动课,让学生在探究“可乐可以除铁锈”本质原因的过程中学习“氧化铁与酸的反应”,从而发展化学学科核心素养,提高解决实际问题的能力。     

信息技术与“教学评”一体化深度融合的教学实践*——以“有机合成”为例

以建构有机合成中的顺推法和逆合成分析法思维模型为载体,通过设置驱动任务,将信息技术和“教学评”一体化深度融合,促进学生结构观、发展观和转化观的形成,理解有机化学的社会价值,培养学生的宏微结合、变化观念、科学态度和社会责任等化学学科核心素养。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

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.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.