Unraveling innate substrate-controlled arylation and bicyclization of 1,5-enynes with α,β conjugates: synthesis of substituted benzo[<i>a</i>]fluorenes
作者:Babasaheb Sopan Gore、Jun-Hao Lin、Jeh-Jeng Wang
DOI:10.1039/d1gc01248g
日期:——
novel strategy for the aromatic C–H functionalization of electron-rich arenes with 1,5-enynes anchored by conjugates, catalyzed by a Brønsted acid under metal- and solvent-free conditions. A diverse range of benzo[a]fluorenes have been realized in moderate to good yields by using this protocol. This process includes intermolecular nucleophilic arene insertion or 6-exo-dig cyclization (depending on
在这里,我们描述了一种新的策略,用于富电子芳烃的芳香族C–H功能化与1,5-炔烃的共轭物锚定,在无金属和无溶剂条件下,由布朗斯台德酸催化。通过使用该协议,已实现了中等至良好收率的多种苯并[ a ]芴。此过程包括分子间亲核芳烃插入或6 -exo-dig环化(取决于底物的性质),然后分别进行Friedel-Crafts型反应和1,5- H转移或分子间亲核芳烃插入。另外,与杂环化合物如(E)-2-苯甲酰基-3-(2-(苯基乙炔基)吡啶-3-基)丙烯腈的反应顺利进行,得到11-苯基-11H-茚并[1,2 - h ]喹啉-6-甲腈类似物。此外,我们成功地展示了绿色途径的溶剂回收实验。这些反应具有易于获得的起始原料,无过渡金属的方法,简单的一锅操作,克级合成和宽泛的官能团耐受性的特点。
A Facile Route to Polysubstituted Naphthalenes and Benzofluorenols
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Scandium Triflate‐ and Triflic Acid‐ Catalyzed Benzannulation of 2‐(2‐Alkynylarylidene)‐ 1,3‐Dicarbonyl Compounds
作者:Lu Liu、Lai Wei、Junliang Zhang
DOI:10.1002/adsc.201000286
日期:2010.10.9
This paper describes an efficient scandium triflate- and triflic acid-catalyzed benzannulation of 2-(2-alkynylarylidene)-1,3-dicarbonyl compounds to afford polysubstitutednaphthalenes and benzo[a]fluorenols. The product selectivity could be tuned by subtle choice of the catalyst. An unprecedented process between alkynes and ketones is also explored.
本文介绍了一种高效的scan酸三氟甲磺酸酯和三氟甲基磺酸催化2-(2-炔基亚芳基)-1,3-二羰基化合物的联苯环化反应,以提供多取代的萘和苯并[ a ]芴醇。产物的选择性可以通过催化剂的精细选择来调节。还探索了炔烃和酮之间前所未有的过程。
Selectivity Control in Lewis Acid Catalyzed Regiodivergent Tandem Cationic Cyclization/Ring Expansion Terminated by Pinacol Rearrangement
作者:Lu Liu、Junliang Zhang
DOI:10.1002/anie.200901628
日期:2009.8.3
Catalyst is key: The title reaction sequence has been carried out on 1 in the presence of AgSbF6 (5 mol %) in DCE or In(OTf)3 (5 mol %) with MeOH (4 equiv) to afford 2 or 3, respectively, in up to >20:1 ratio (see scheme; DCE=1,2‐dichloroethane, Tf=trifluoromethanesulfonyl).