基于深度学习理论的有机合成课程教学改革

有机合成既是有机化学学习中的一个独立构成部分,也是安排于有机化学课程之中的重要学习主题。在目前的有机合成课程教学中,教师的自觉性引导不足,学生容易陷入浅层学习状态,导致教学效果不佳。结合有机化学学科特点,从有机合成课程教学现状出发,围绕深度学习教学设计的四要素——深度学习目标、挑战性学习主题、深度学习活动、持续性评价,以典型的教学片段为例阐述深度学习理论在教学实践中的应用,为相关教学工作提供参考。     

基于实际问题解决的深度教学*——以“酸、碱、盐复习”为例

基于深度学习理念,对酸、碱、盐复习进行了设计。以灭火器原理探究为主线,以实验探究活动为主导,引导学生应用所学知识鉴别盐酸和硫酸,并运用阅读、分析信息的能力及对知识的迁移能力鉴别碳酸钠和碳酸氢钠,以达到培养学生高阶思维的目的。     

基于图形组织者的深度学习研究与实践*——以无机化学课程为例

在无机化学教学中引入图形组织者,引导学生使用不同图形组织者来整理和激发思维,构建思维网络,实现深度学习。实践表明,这种教学策略可有效激发学生的学习动机,促进深度学习的产生,对学生高阶思维能力和自主学习能力的养成起到积极作用。     

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。     

基于思维导图的先行组织者支架在化学教学中的应用

教学中教师为了完成教学任务会忽视学生的高阶思维发展的培养,这样做虽然教学目标可以及时完成,但是教学效果会大打折扣,更重要的是直接阻碍了创新及批判性思维、获得隐性知识、自我管理等高阶能力的发展。高阶思维需要高阶学习支架支持,以“基于思维导图的先行组织者支架”在不同课型中的运用,帮助学生参与复杂的认知活动,进而建立高阶思维模型和提升元认知水平。     

指向深度学习的高三化学实验复习*——葡萄糖酸锌的制备及纯度测定

针对当前高三化学实验常态复习难以适应“素养为本”的实验试题考查要求的现状,提出了以深度学习指引高三化学实验有效复习的设计思路:精选学习主题、设计学习任务、进行实时评价,并以“七水合硫酸锌的制备、葡萄糖酸锌的制备、葡萄糖酸锌的纯度测定、构建认知模型”为主线,设计了“葡萄糖酸锌的制备及纯度测定”一课,为高三化学实验的深度复习提供了可资借鉴的设计思路和教学案例。     

以深度的科学探究促进初中生高阶思维能力发展*——以“酸和碱的中和反应”为例

针对学生在学习“酸和碱的中和反应”中普遍存在的“被动接受具体知识、缺失开展真实科学探究的思路、机械记忆中和反应规律、缺乏批判质疑精神及高阶思维能力不足”等倾向问题,设置了驱动性问题链协助学生搭建“情境问题”与“真实的科学探究”间的思路桥梁,在深度的科学探究中发展学生的发散性思维、有序思维、多角度分析问题、设计创造思维、逻辑严密的推理及评价反思等高阶思维能力。课堂教学中营造轻松、舒适的交流讨论环境,有益于学生之间碰撞出思维的火花、激发出创造的灵感。课堂观察表明,深度科学探究教学的实施,有效提升了学生的高阶思维能力及解决问题的能力。     

高三复习课“氧化还原反应”的教学实录与反思

基于实证,设计了“氧化还原反应”高三复习课,以“污水处理”为主题,通过创设真实情境,激发生成问题,开展有效活动,引导学生在知识应用中加深对知识的理解,促进知识重构和认识转变,力求实现从虚拟走向真实,从学科走向学生,从经验走向科学,从教学走向教育。     

宏观把握微观掌握──利用思维导图上好化学复习课

介绍了在化学复习课教学中,如何利用思维导图从课前、课中和课后3个阶段引导学生对知识进行系统化的整理,以形成知识体系,并从细节上把握各知识点的应用;同时探讨了思维导图在复习课教学方面的优势。     

基于思维模型建构的高三化学复习教学*—— 以“平衡原理的应用”为例

以高三复习课“平衡原理的应用”为例,通过真实情境的剖析让学生感知模型,引导学生分析归纳提炼模型,并进行针对练习运用模型,变式训练体会模型,让学生在实践中以模型思维为突破,深入领悟建构模型的实质,有序解决复杂化学问题,提升科学思维能力,发展化学学科核心素养。     

Synthesis of O-glycosylα-aryl nitrones

<正>α-Aryl nitrone are one of the most useful kinds of nitrones and have been extensively explored in recent years.However,the sugar moieties have not been introduced into these molecules before.We presented here an efficient synthesis ofα-aryl nitrone Oglycosides via condensation of N-substituted hydroxylamine and aryl aldehydes glycosides in benzene.     

Synthesis of 2′-dealkylmumbaistatin

The sterically congested 1,2,3-substituted 3′-dealkyl mumbaistatin derivatives 16, 20, and 21 were prepared for the first time by base-catalyzed cyclization of the 2,3-bis-substituted naphthoquinone precursor 11 followed by bromine mediated photooxidation and methyl ether cleavage.     

Synthesis of Barleriaquinones-I & II

Synthesis of two naturally occurring anthraquinones, Barleriaquinone-I (BQ-I) and Barleriaquinone-II (BQ-II) is achieved from commercially available naphthalene-1,5-diol. The anthraquinone core is constructed by utilizing simultaneous Heck and cross coupling reaction as the key step.     

Synthesis of Glycocinnasperimicin D

The first total synthesis of amino sugar antibiotic glycocinnasperimicin D ( 1 ) has been achieved by a convergent, three‐component coupling strategy. The key steps involve the Heck–Mizoroki reaction by using the iodophenyl glycoside 50 and acryl amide 32 to furnish the right core structure of 1 , and the construction of the urea glycoside employing the reaction of glycosyl isocyanate 8 with amino sugar 9 . Glycosyl isocyanate 8 was prepared by the oxidation of isonitrile 10 , which displayed excellent reactivity in the coupling event. Synthetic roadblocks, encountered during this synthetic effort, have led to the development of the α‐selective, Lewis acid catalyzed phenyl glycosylation process with 2‐amino‐hexopyranose and a procedure for acetonide deprotection without affecting the silyl ethers.     

Synthesis of Privileged Scaffolds by Using Diversity‐Oriented Synthesis

An elegant reagent‐controlled strategy has been developed for the generation of a diverse range of biologically active scaffolds from a chiral bicyclic lactam. Reduction of the chiral lactam with LAH or alkylation with LHMDS to trigger different cyclization reactions have been shown to generate privileged scaffolds, such as pyrrolidines, indolines, and cyclotryptamines. Their amenability to substitution allows us to create various compound libraries by using these scaffolds. In silico studies were used to estimate the drug‐like properties of these compounds. Selected compounds were subjected to anticancer screening by using three different cell lines. In addition, all these compounds were subjected to antibacterial screening to gauge the spectrum of biological activity that was conferred by our DOS methodology. Gratifyingly, with no additional iterative cycles, our method directly generated anticancer compounds with potency at low nanomolar concentrations, as represented by spiroindoline 14 .     

Synthesis of 5′-seleno-xylofuranosides

The synthesis of selenium derivatives of naturally occurring chiral molecules is becoming increasingly important in recent years. In this context, we describe herein an easy, straightforward synthetic route for the preparation of a series of chiral seleno-furanosides, starting from the readily available carbohydrate d-xylose. In addition, selected compounds were screened as inhibitors of the δ-aminolevulinate dehydratase (δ-ALA-D) enzyme. Diselenide 4 was found to reduce significantly the enzymatic activity, while seleno-furanoside 1a increased δ-ALA-D activity.     

The Synthesis of Racemic Ambrox®

(±)-Ambrox ( 10 ), the racemic form of (?)-Ambrox®, the commercially most important ambergris odorant has been synthesized from a readily available bicyclic keto ester in five steps. The racemic ether retains the characteristic scent of fine-quality ambergis, and the odor threshold of the racemate and the (?)-enantiomer prepared from natural sclareol were found to be essentially identical.     

Synthesis of polybutadiene–polysulphide

The anionic synthesis of polybutadiene–polysulphide polymers from butadiene, elemental sulphur, and sodium was studied in a polar solvent (THF). The polycondensation results from the combination of three reactions: initiation of the monomer by the alkali metals, anionic propagation, and deactivation of the dianionic species on elemental sulphur. From the characterization of the resulting polymers it has been shown that the sulphur rank of the polymer can be adjusted by varying the ratio K = [sodium]/[sulphur]. The degree of polymerization of the organic chain can be controlled by changing the temperature or the monomer concentration. From the thiol content, it has been concluded that the polysulphide polymers are principally in a cyclic form. It was also observed that the formation of the 1,4-structure for the butadiene unit is quantitative when the deactivation of the corresponding carbanions occurs on elemental sulphur.