A General Protocol toward Oxindoles Bearing C3-Allylic Quaternary Stereocenter via Domino Reaction:A Concise Synthesis of Heterocycle-Fused Indoline Alkaloids

An efficiently catalytic method toward the synthesis of indolin-2-ones featuring an allylic derived C3-quaternary stereocenter via an intramolecular Heck cyclization/Suzuki coupling of N-substituted-N-(2-bromophenyl)acrylamides and organoboron reagents was successfully developed by using a 1,3-bis(2,6-diisopropylphenyl)acenaphthoimidazol-2-ylidene(AnIPr)-ligated oxazoline palladacycle.It enabled a very broad substrate scope tolerating different functional groups,electronic properties and steric bulkiness.Notably,it revealed a great potential to build diverse heterocycle-fused indoline alkaloids via the same intermediate 3-allyl-1,3-dimethylindolin-2-one.

An Efficient Asymmetric Domino Reaction of Amino Aldehyde to β,γ-Unsaturated a-Keto Esters Using trans-Perhydroindolic Acid as a Chiral Organocatalyst

An efficient asymmetric domino reaction of amino aldehyde to β,γ-unsaturated a-keto esters was achieved by using trans-perhydroindolic acid ld as a chiral organocatalyst with excellent asymmetric behavior. Under the opti- mal reaction conditions, products with more than 99% de and up to 93% ee were obtained in high chemical yield （up to 98%） for a series of β,γ-unsaturated a-keto esters. The methodology provided an efficient route to dihydro- pyran derivatives containing many substituent groups （including amino groups）.

Radical cation salts induced domino reaction of anilines with enol ethers:Synthesis of 1,2,3,4-tetrahydroquinoline derivatives

A domino reaction of anilines with cyclic and acyclic enol ethers induced by catalytic amounts of TBPA^（·＋）（5 mol%） was investigated and a series of 2,4-disubstituted-1,2,3,4-tetrahydroquinolines were synthesized.Different from cyclic enol ethers, when acyclic enol ethers were used in the reaction,they serve as surrogates of acetaldehyde,producing a series of 2-methyl-4- anilino-1,2,3,4-tetrahydroquinolines.A single electron transfer mechanism was proposed to rationalize the products formation.

Diastereoselective Synthesis of Arylidene Bis（3-arylamino- acrylates） via One-pot Domino Reactions

The functionalized arylidene bis（3-arylaminoacrylates） were efficiently prepared by FeCl3 catalyzed one-pot domino reactions of primary amines, methyl propiolate and aromatic aldehydes. When isatins were utilized under similar conditions, only 2-oxoindolinyl 3-arylaminoacrylates were obtained in moderate yields. ^1H NMR data and single crystal structures indicated that this reaction has high diastereoselectivity.

Copper Hydride-Catalyzed Conjugate Reduction-Aldol Addition Domino Reaction of α,β-Unsaturated Carboxylates with Ketones

Copper hydride-catalyzed conjugate reduction-intermolecular aldol addition domino reactions were realized using α,β-unsaturated carboxylates as hydride acceptors and a silane as the reducing reagent. High diastereoselec- tivities were achieved with 4,5-bis（diphenylphosphino）-9,9-dimethylxanthene as the ligand and tert-butyl acrylate as the hydride acceptor.

Application of Functionalized N,S-Ketene Acetals Microwave- Assisted Three-Component Domino Reaction for Rapid Direct Access to Imidazo[1,2-a]pyridines

Imidazo[1,2-a]pyridines have been successfully synthesized in moderate to good yields via a tandem three- component reaction of ethyl 2-（3-oxo-3-arylpropanethioamido）acetates with aromatic aldehydes and malononitrile by means of microwave irradiation using DABCO as the catalyst. The advantages of this method including high chemo- and regioselectivity make this new strategy highly attractive.

One-Pot Synthesis of Aliphatic Nitro Compounds by Michael/retro-Claisen Fragmentation Domino Reaction

A novel and concise method for the construction ofγ-nitro ketones and 1,3-dinitro compounds with chemo-selective acyl transfer has been presented under basic conditions via one-pot reactions.These reactions feature high atom-and step-economic possess,mild condition and simple operation for one-pot synthesis of aliphatic nitro compounds.This protocol provides the products in good yields.The possible reaction mechanism has also been proposed.

Intramolecular α-Oxygenation of Amines via N-Heterocyclic Carbene-Catalyzed Domino Reaction of Aryl Aldehyde: Experiment and DFT Calculation

We have developed an N-heterocyclic carbene(NHC)-catalyzed domino reaction with aryl alde-hyde through a simple acyl azolium intermediate using phenyliodine(III)diacetate(PIDA)as an oxi-dant.Controlled experiments and density functional theory calculations supported a domino two-stage mechanism from aldehyde/amine to anα-oxygen-ation product,including NHC-catalyzed oxidation of the aldehyde to carboxylic acid via acyl azolium intermediate,and further,an addition of carboxyl-ate to iminium intermediate.Our study reveals a new model for the oxidation of Breslow intermedi-ate via electrophilic attack of the hydroxyl group by PIDA.

Synthesis of trifluoromethyl-/cyclopropyl-substituted 2-isoxazolines by DBU-promoted domino reaction

NTrifluoromethyl and cyclopropyl substituted 2-isoxazolines were synthesized via a DBU-promoted domino reaction of β-trifluoromethyl-/β-cyclopropyl-substituted enones with hydroxylamine. The domino reaction consists of a Michael addition and the followed cyclization. A wide range of 3-substituted 5-cyclopropyl-5-trifluoromethyl-2-isoxazolines were obtained in good to excellent yields under mild reaction conditions. The method could also apply to other trifluoromethyl-substituted enones.

DABCO-catalyzed multi-component domino reactions for green and efficient synthesis of novel 3-oxo-3H-benzo[a]pyrano[2,3-c]phenazine-1-carboxylate and 3-(5-hydroxybenzo[a]phenazin-6-yl)acrylate derivatives in water

An efficient,convenient and environmentally benign procedure for the synthesis of novel 3-oxo-3Hbenzo[a]pyrano[2.3-c]phenazine-l-carboxylate and 3-（5-hydroxybenzo[a]phenazin-6-yl） acrylate derivatives has been developed by domino three-component condensation reaction between 2-hydroxynaphthalene-1,4-dione,benzene-1,2-diamines and acetylenic esters in the presence of a catalytic amount of DABCO as an expedient,eco-friendly and reusable base catalyst in water.This green process produces biologically and pharmacologically significant heterocycles in a one-pot single operation and offers considerable advantages such as：operational simplicity,short reaction time,high yields,reusability of catalyst,absence of any tedious workup or purification and avoids hazardous reagents/solvents.

钯-手性磷酸接力催化的一锅三步串联反应合成手性四氢喹啉

设计钯-手性磷酸接力催化体系,以邻碘苯胺和苯基烯丙醇为原料,通过“一锅三步”串联反应高效合成手性2-苯基四氢喹啉,实验无需中间体分离,降低了手性四氢喹啉的合成难度并提高反应经济性,与单一催化反应相比,协同接力催化具有操作简单、反应高效等优点。将协同接力催化的科学前沿引入本科实验教学,融入节能减排和绿色化学等课程思政元素,能拓宽学生的科学视野,激发其学习兴趣并提升创新能力。此外,实验涵盖格氏反应、Heck反应、亚胺缩合反应、不对称氢转移反应等理论知识以及薄层色谱、柱层析色谱、旋转蒸发仪、核磁共振仪、高效液相色谱仪、旋光仪等分析分离设备的操作使用,能综合提升学生的理论水平、实验技能和科学思维能力,促进科研与教学相融合。

三组分串联反应区域选择性合成双吲哚衍生物

报道了一种微波辅助的区域选择性反应,该反应从芳酮醛水合物、N-芳基烯胺酮和吲哚出发,通过改变取代的吲哚底物来获得3,2′-和3,3′-双吲哚衍生物。该方法具有区域选择性高、反应时间短、操作简单等显著优点。

Zirconyl Chloride Promoted Highly Efficient Domino Synthesis of New 1, 2, 3, 4-Tetrahydroquinoline Derivatives in Water

The tetrahydroquinoline moiety is a structural feature of many natural products. By using a domino reaction of aromatic amines and cyclic enol ethers catalyzed by zirconyl chloride in water, various tetrahydroquinoline derivatives were synthesized efficiently. Most cyclized products showed cis selectivity. The cis selectivity was tentatively rationalized due to chelation control in water.

Synthesis of Polysubstituted 1,4-Dihydropyridines via Four-component Reactions of Arylamine,Acetylenedicarboxylate, Aromatic Aldehyde and Ethyl Acetoacetate

An efficient synthetic protocol for the 1,4-diaryl-1,4-dihydropyridines was developed via the domino four-component reaction of arylamine,acetylenedicarboxylate,aromatic aldehyde and ethyl acetoacetate.The reaction mechanism involves the formation of β-enamino ester and its sequential Michael addition to arylidene acetoacetate.

经由Domino脱HCl/Pd(OAc)_2催化的Heck反应合成查尔酮(英文)

通过Domino脱HCl/Pd(OAc)2催化的Heck反应实现了β-氯代烷基芳基酮、酯和酰胺与卤代芳烃的交叉偶联反应,高效合成了查尔酮类化合物.利用原位生成烯酮为中间体进行反应的策略,减少副反应的发生,从而提高反应的效率.该方法对各种官能团的容忍性好,为从氯代烷烃出发直接合成查尔酮类化合物提供了一条新途径.

串联[3+2]环加成和丁炔二甲酸酯参与的扩环反应合成新型螺吲哚酮和螺二氢喹啉类化合物

因具有原料易得、方法简便、反应步骤和分离步骤少等特点,多组分反应和串联反应在有机合成中获得广泛的应用。本文报道一种简洁高效的串联反应合成螺环化合物的新方法。通过硫代脯氨酸、靛红和双查尔酮先在甲醇中进行[3+2]环加成反应,然后在甲醇回流条件下与丁炔二酸二甲酯通过扩环反应,分别生成了结构新颖的含巯基的螺吲哚酮化合物和螺二氢喹啉衍生物,其结构经IR,HR-MS,^(1)H NMR和^(13)C NMR表征,并确定了单晶分子结构。该反应具有原料简单易得,操作简便,原子经济性高等优点。

有机实验课程设计:三组分串联反应高效合成苯并噻吩衍生物

串联反应大大减少有机反应中间体分离提纯所需要的有机溶剂,可以缩短反应步骤,降低人力成本,符合当今时代发展问题所提出的“双碳”目标。目前,多组分串联反应在大学有机化学中普及程度不高,因此为了让本科生对绿色化学的观念理解的更加广泛,设计了一个适合在各高校推广的本科有机实验方案,以硫代靛红、溴代苯乙酮和哌啶为反应物,无需使用催化剂,在室温下三组分串联反应高效合成苯并噻吩类产物。通过TLC和硅胶层析柱对产物进行纯化,利用核磁共振波谱(NMR)和单晶衍射对产物进行结构确定,对反应机理进行推测。培养本科生综合实验的设计和完成能力,初步探索复杂反应机理的能力。

螯合型杂芳基甲胺串联合成双核钴1,4-二氢吡嗪配合物过程跟踪与机理研究

为了探索3d过渡金属离子配位导向鳌合型芳基甲胺的串联反应,拓展芳基甲胺的配位-自缩合-环加成反应序列,选取了2种底物:苯并[d]噻唑基-2-甲胺(S1)和(1-甲基-1H-苯并[d]咪唑-2-基)甲胺(L1),研究其与CoCl_(2)·6H_(2)O在120℃溶剂热条件下的反应。该反应并没有获得和以往类似的吡嗪衍生物,而是得到了含有1,4-二氢吡嗪配体的双核钴配合物2(化合物2):[CoCl(HPy)]_(2)(HPy^(-):2,2′,2″-(6-(1-甲基-1H-苯并[d]咪唑-2-基)-1,4-二氢吡嗪-2,3,5-三基)三(苯并[d]噻唑)阴离子)。通过X射线单晶衍射、X射线光电子能谱和红外光谱技术,证明化合物2中具有去质子化的1,4-二氢吡嗪阴离子(HPy^(-))有机骨架。利用电喷雾离子化质谱对反应溶液进行跟踪,检测到了一系列关键中间体片段(i、ii和[1-CoCl_(2)+H]^(+)),结合控制实验提出了可能的反应机理,包括S1和L1分别与Co^(2+)配位、胺的氧化自缩合以及交叉缩合、[3+3]环加成等5步连续转化。该反应实现了6个共价键(4个σ键和2个π键)的连续构筑。同时,Co^(2+)与1,4-二氢吡嗪中N原子的配位作用稳定了1,4-二氢吡嗪环,表明基于3d过渡金属离子配位导向的芳香甲胺的氧化缩合-环加成串联序列是合成新颖杂环非常有潜力的策略,在串联反应的设计、杂环的性质研究等方面有重要的应用前景。

基于2-甲酰基苯并噻唑与2-氨甲基吡啶串联合成四取代吡咯衍生物及其光学性质研究

串联反应可以从简单原料经简单步骤直接获得结构复杂的化合物,具有很高的原子经济性。同时节省能源、人力、时间、及溶剂的使用,吸引了越来越多化学家的研究兴趣。本文利用2-甲酰基苯并噻唑(L1)和2-氨甲基吡啶(L2)在FeCl_(2)·4H_(2)O的存在下的溶解热反应,“一锅”串联合成了四苯并噻唑取代的吡咯衍生物3。化合物3经过X-射线单晶衍射和红外光谱表征,并且对光学性质进行了初步研究,发现其紫外-可见光谱的最大吸收峰分别在382 nm和413 nm,荧光发射光谱的最大发射波长在433 nm和515 nm。该工作表明,基于Fe^(2+)离子配位导向的杂芳基甲醛与杂芳基甲胺之间的串联反应,可以直接获得结构复杂且新颖的杂环聚集体,为有机合成等领域提供新的研究对象且具有潜在的应用价值。