有效合成3-(1-(2-(1 H-吲哚-3-基)乙基)-2-芳基-6,6-二甲基-4-氧代4,5,6,7-四氢-1使用新制备的核-壳纳米结构,在超声波照射下,3-苯甲酰亚氨基新吲哚,色胺和二甲酮的一锅三组分反应报告了H-吲哚-3-基)吲哚-2-酮。利用的纳米催化剂是通过将磺化的L-组氨酸氨基酸壳作为生物部分固定在二氧化硅-纳米磁铁矿芯(SO 3 H- L - His @ SiO 2-纳米Fe 3 O 4)上,并通过傅里叶变换红外光谱进行表征的,核磁共振波谱学(1H NMR),场发射扫描电子显微镜,能量分散X射线光谱,热重/差热分析,振动样品磁力计测量,透射电子显微镜和反滴定。该协议具有以下优点:反应时间相对较短,通过催化剂与外部磁体的分离而简化的后处理程序,使用经济和环保的超声波以及核壳纳米促进剂的可重复使用性和可回收性进行三轮运动,没有明显的活动损失。
A New [2+2+1] Heterocyclization for the Synthesis of 2,3,5-Trisubstituted Thiophenes under Microwave Irradiation
作者:Bo Jiang、Shu-Jiang Tu、Hai-Wei Xu、Guan-Hua Ma
DOI:10.1055/s-0033-1339917
日期:——
Abstract A new three-component strategy for the efficient synthesis of 2,3,5-trisubstituted thiophene derivatives through a [2+2+1] heterocyclization between 3-(2-aryl-2-oxoethylidene)-2-oxindoles and α-thiocyanato ketones under microwave irradiation is described. The bond-forming efficiency, accessibility, and generality of this synthesis make it highly valuable to assemble thiophene scaffolds. A new three-component
A formal [1 + 2 + 3] annulation of methyleneindolinones with o-alkenyl arylisocyanides has been developed for the general and efficient synthesis of both symmetrical and unsymmetrical indolo[3,2-b]carbazoles. The chemoselectivity of this domino reaction was tuned by a tethered alkenyl group, which enables successive formation of three new bonds and two rings from readily accessible starting materials
已开发了一种亚甲基吲哚酮与邻链烯基芳基异氰酸酯的正式[1 + 2 + 3]环合结构,用于对称和不对称的吲哚[3,2- b ]咔唑的常规合成。该多米诺反应的化学选择性通过束缚链烯基进行调节,该链烯基能够在一次操作中由易于接近的起始原料连续形成三个新键和两个环。此外,该方法被用作生物碱麦拉西唑C合成中的关键步骤。
Hauser‐Kraus Annulation Initiated Multi‐Cascade Reactions for Facile Access to Functionalized and Fused Oxazepines, Carbazoles and Phenanthridinediones
作者:Chenikkayala Siva Sankara、Irishi N. N. Namboothiri
DOI:10.1002/chem.202303517
日期:2024.1.11
ne-7,12-dione are accessible by a base mediatedreaction of 3-olefinic oxindole with 3-nucleophilic phthalide. This cascadesynthesis involved several regioselective steps such as Hauser-Kraus annulation, ring cleavage (C−Cσ), ring expansion, ring opening and ring contraction reactions in one pot. The formation of a new compound at every stage of the reaction by forming multiple new chemical bonds
正轨前进。一些含氮芳族杂环,例如二氢苯并[ d ]萘并氧杂氮卓、苯并[ a ]咔唑和苯并[ j ]菲啶-7,12-二酮可通过3-烯属羟吲哚与3-亲核苯并呋喃酮的碱介导反应获得。这种级联合成涉及几个区域选择性步骤,例如一锅中的 Hauser-Kraus 成环、环裂解 (C−Cσ)、环扩展、开环和环收缩反应。在反应的每个阶段,通过形成多个新的化学键,同时继续生成标题化合物,形成新的化合物,这是该反应序列的另一个亮点。此外,该转化产生稳定且可分离的介质环。通过分离所有稳定的中间体并将其转化为目标化合物以及通过对照实验,反应的完整机理得到了合理化。