Triflic acid-promoted cycloisomerization of 2-alkynylphenyl isothiocyanates and isocyanates: a novel synthetic method for a variety of indole derivatives
A new approach towards the synthesis of indolederivatives via triflic acid-promoted cycloisomerization with rearrangement of 2-(alkyn-1-yl)phenylisothiocyanates and 2-(alkyn-1-yl)phenylisocyanates has been achieved. By this methodology, structurally diverse types of indolederivatives such as thieno- and furo-indoles, spiro-indolethiones, spiro-oxindoles, and 3-alkylidene-oxindoles were synthesized
Biradicals from Thermolysis of <i>N</i>-[2-(1-Alkynyl)phenyl]-<i>N</i>‘-phenylcarbodiimides and Their Subsequent Transformations to 6<i>H</i>-Indolo[2,3-<i>b</i>]quinolines
作者:Chongsheng Shi、Quan Zhang、Kung K. Wang
DOI:10.1021/jo981845k
日期:1999.2.1
Thermolysis of the carbodiimide 9a in gamma-terpinene at 138 degrees C produced 2-(phenylamino)quinoline (11a, 49%) and the parent 6H-indolo[2,3-b]quinoline (14a, 16%). Apparently, 11a was produced via the biradical 10a followed by hydrogen-atom abstraction from gamma-terpinene. A two-step biradical pathway through 12a or a one-step intramolecular Diels-Alder reaction could furnish 13a, which then
碳二亚胺9a在138℃下在γ-萜品烯中的热解产生2-(苯氨基)喹啉(11a,49%)和母体6H-吲哚并[2,3-b]喹啉(14a,16%)。显然,通过双自由基10a生成11a,然后从γ-萜品烯中提取氢原子。通过12a的两步双自由基途径或一个分子内Diels-Alder反应一步可提供13a,然后将其进行互变异构化得到14a。对于在乙炔基末端具有三甲基甲硅烷基取代基的碳二亚胺9b,在138℃下在回流的对二甲苯中热解仅产生6H-吲哚并[2,3-b]喹啉14b(86%)。在回流的乙醇中用6 N NaOH处理14b,然后以92%的收率得到14a。类似地,通过碳二亚胺9c-f的热解获得6H-吲哚并[2,3-b]喹啉14c-f。通过使用4-甲氧基苯基异氰酸酯与亚氨基膦酸酯2d和2f之间的氮杂-维蒂希反应来产生相应的碳二亚胺,然后进行热分解,得到在C上具有甲氧基取代基的6H-吲哚并[2,3-b]喹啉16d和16f。
Brønsted Base-Catalyzed Reductive Cyclization of Alkynyl α-Iminoesters through Auto-Tandem Catalysis
作者:Azusa Kondoh、Masahiro Terada
DOI:10.1021/acs.orglett.8b02236
日期:2018.9.7
auto-tandem catalysis with a Brønsted base as the catalyst. The reaction system involves two mechanistically different elementary processes, both of which are efficiently catalyzed by an organosuperbase P2-tBu: the unprecedented reduction of α-iminoesters with 1-dodecanethiol as the reductant to provide α-aminoesters and the following intramolecular addition of ester enolates to an alkyne. The operationally
通过以布朗斯台德碱为催化剂的自动串联催化,开发了炔基α-亚氨基酸酯的新型还原环化反应。反应系统涉及两个机理上不同的基本过程,有机超碱P2- t Bu有效地催化了这两个过程:以1-十二烷硫醇为还原剂的α-亚氨基酯的空前还原以提供α-氨基酯,以及随后在分子内添加酯烯醇成炔。在温和条件下操作简单的反应为N -H二氢吲哚衍生物提供了新的有效途径,证明了使用Brønsted碱作为有机合成方法的自动串联催化的巨大潜力。
Efficient Regioselective Synthesis of Indole <i>N</i>-Carboximidamides and <i>N</i>-Carboximidoates by a Sequential Aza-Wittig/Ag(I)-Catalyzed Cyclization
作者:Nian-Yu Huang、Ming-Guo Liu、Ming-Wu Ding
DOI:10.1021/jo901362c
日期:2009.9.4
An efficient Ag(I)-catalyzed regioselectivecyclization of (2-alkynylphenyl)guanidine or (2-alkynylphenyl)isourea to indole N-carboximidamides or N-carboximidoates has been developed. The approach has the advantages of high regioselectivity, mild reaction conditions, easily accessible starting materials, and good yields.
Tandem Synthesis of Benzo[<i>b</i>]carbazoles and Their Photoluminescent Properties
作者:Yanpeng Xing、Binbin Hu、Qijun Yao、Ping Lu、Yanguang Wang
DOI:10.1002/chem.201301887
日期:2013.9.16
5 H‐Benzo[b]carbazoles were prepared through a tandem reaction between 2‐ethynyl‐N‐triphenylphosphoranylidene anilines and α‐diazoketones through ketenimine intermediates in moderate‐to‐good yields. By using this approach, benzo[b]benzo[5,6]indolo[3,2‐h]carbazoles, fluoreno[9,1‐ab]carbazoles, and fluoreno[9,1‐ab]fluoreno[1′,9′:5,6,7]indolo[3,2‐h]carbazoles were constructed in one pot. Moreover, the
通过2-乙炔基-N-三苯基磷酰亚苯胺苯胺和α-二氮酮通过酮亚胺中间体的串联反应,以中等至良好的产率制备了5 H-苯并[ b ]咔唑。通过使用这种方法,苯并[ b ]苯并[5,6]吲哚并[3,2- h ]咔唑,芴[9,1- ab ]咔唑和芴[9,1- ab ]氟[1',9 ′:5,6,7] indolo [3,2- h ]咔唑是在一个锅中制成的。而且,最终产物发出的光在410-521 nm范围内,量子产率高达62%。