The photolysis of substituted o-divinylbenzenes promotes a one-step and metal-free conversion to oxatricycles at room temperature. Irradiation o-divinylbenzenes results in an pericyclic reaction to form cyclic o-quinodiemthane intermediates, which subsequently undergo intramolecular oxa-[4+2] cycloaddition to form oxacyclic derivatives.
Acid-Mediated Cascade Cyclization Pathway to Indeno[2,1-<i>c</i>]chromen-6(7<i>H</i>)-ones
作者:Chander Shekhar、Gedu Satyanarayana
DOI:10.1021/acs.joc.3c01459
日期:2023.10.6
effective synthetic strategies for producing significant molecules starting from readily available starting materials is indispensable in organic synthesis. Herein, we present a triflic acid-driven dual cyclization pathway to produce functionalized indeno[2,1-c]chromen-6(7H)-ones from simple 2-formyl (or 2-acyl) cinnamate esters and phenols. Notably, this protocol enabled the construction of two C–C bonds and
开发温和有效的合成策略,从容易获得的起始材料开始生产重要的分子,在有机合成中是必不可少的。在此,我们提出了一种三氟甲磺酸驱动的双环化途径,从简单的2-甲酰基(或2-酰基)肉桂酸酯和酚类生产功能化的茚并[2,1- c ]色烯-6(7 H )-酮。值得注意的是,该方案通过在单锅中激活非反应性酯部分,能够在无金属反应条件下构建两个 C-C 键和一个 C-O 键。中间体茚醇酯的分离可能表明通过烯酸酯的邻近双键与邻羰基部分进行自分子内环加成,随后用苯酚进行亲电攻击以及随后的环缩合途径。此外,还检查了光物理性质。
Acid-Promoted Domino Access to Substituted Benzo[<i>b</i>]carbazoles
作者:Chander Shekhar、Gedu Satyanarayana
DOI:10.1021/acs.joc.3c02483
日期:2024.3.15
studies suggested the initial formation of bis-indole substituted intermediate via a dual aromatic substitution with two indole molecules at the carbonyl carbon of ortho-formyl (or ortho-acyl) cinnamate ester followed by intramolecular cyclization and aromatization with exclusion of a second indole molecule. Besides, the efficacy of this approach was also illustrated by scale-up and derivatization reactions
在此,从容易获得的邻甲酰基(或邻酰基)肉桂酸酯和吲哚描述了一种直接的布朗斯台德酸促进的多米诺骨牌途径来构建取代的苯并[ b ]咔唑。值得注意的是,该方案适合保护无基团的吲哚。值得注意的是,该方法基于在温和且无金属的反应条件下单锅区域选择性构建两个新的 C-C 键和芳构化序列。机理研究表明,通过在邻甲酰基(或邻酰基)肉桂酸酯的羰基碳上用两个吲哚分子进行双重芳族取代,最初形成双吲哚取代中间体,然后进行分子内环化和芳构化,排除第二个吲哚分子。此外,还通过放大和衍生反应(包括光物理性质研究)说明了该方法的有效性。
Efficient synthesis of polysubstituted isochromanones via a novel photochemical rearrangement
作者:Wujiong Xia、Yutian Shao、Weijun Gui、Chao Yang
DOI:10.1039/c1cc14269k
日期:——
A novel and convenient approach to the synthesis of polysubstituted isochromanones is described. Irradiation of 2-formyl phenylalkeno-derivatives with UV light in benzene solution afforded the corresponding products in up to 98% yield. The possible reaction mechanism is proposed and further supported by the isotopic experiments.