C=C-conjugated carbodiimides as 2-aza dienes in intramolecular [4+2] cycloadditions. One-pot preparation of quinoline, .alpha.-carboline, and quinindoline derivatives
摘要:
Iminophosphoranes 2 derived from o-aminostyrenes react with aryl isocyanates to give the corresponding carbodiimides 13 which by thermal treatment at 160-degrees-C undergo 6-pi-electrocyclization to give quinoline derivatives 14. However, the reaction with styryl isocyanates leads to alpha-carbolines 19 through the intermediate carbodiimides 15 which undergo a tandem intramolecular hetero-Diels-Alder cycloaddition/aromatization process to give 19. Similarly, related alpha-carbolines 20-22 can be obtained from the reaction of iminophosphoranes derived from ortho-substituted anilines containing an unsaturated side chain with styryl isocyanates. Iminophosphorane 6a, derived from o-butadienylaniline, and related 10 and 12 react with aryl isocyanates under the same reaction conditions to give quinindoline derivatives 25-27, respectively. Finally, iminophosphoranes 2 and 6 by reaction with ketenes lead directly to quinolines 32 and benzo[b]carbazoles 33, respectively.
Microwave-induced bismuth(III)-catalyzed synthesis of linear indoloquinolines
作者:Prakash T. Parvatkar、P.S. Parameswaran、Debasish Bandyopadhyay、Sanghamitra Mukherjee、Bimal K. Banik
DOI:10.1016/j.tetlet.2017.06.040
日期:2017.7
Bi(NO3)3-catalyzed one-pot synthesis of a series of linear indoloquinolines is accomplished under mild reactionconditions. While majority of these examples were carried out undersolvent-freeconditions, in a few cases, minimal quantity of THF is used as solvent. The methodology involves several unique reaction pathways, providing different linear indolo[2,3-b]quinolines in good yields from readily
微波诱导的Bi(NO 3)3催化一锅合成一系列线性吲哚喹啉在温和的反应条件下完成。尽管这些示例中的大多数都是在无溶剂条件下进行的,但在少数情况下,使用的THF量很少。该方法涉及几种独特的反应途径,从容易获得的起始原料中以高收率提供不同的线性吲哚并[2,3- b ]喹啉,并使用对环境无害的Bi(NO 3)3 ·5H 2 O作为催化剂。
An Expeditious I<sub>2</sub>-Catalyzed Entry into 6<i>H</i>-Indolo[2,3-<i>b</i>]quinoline System of Cryptotackieine
作者:Prakash T. Parvatkar、Perunninakulath S. Parameswaran、Santosh G. Tilve
DOI:10.1021/jo901361x
日期:2009.11.6
A synthesis of a series of novel 6H-indolo[2,3-b]-quinolines with different substituents on the quinoline ring is described. The method involves reaction of indole-3-carboxyaldehyde with aryl amines in the presence of a catalytic amount of iodine in refluxing diphenyl ether to yield indolo[2,3-b]quinolines in one-pot. The present approach provides a new route for the synthesis of polycyclic structures related to an alkaloid cryptotackieine (neocryptolepine).
Ruthenium-exchanged FAU-Y zeolite catalyzed improvement in the synthesis of 6H-indolo[2,3-b]quinolines
作者:Alireza Khorshidi、Khalil Tabatabaeian
DOI:10.1016/j.molcata.2011.05.010
日期:2011.6
Ruthenium-exchanged FAU-Y zeolite (RuY) was used as a recyclable catalyst for preparation of 6H-indolo[2,3-b]quinolines from the reaction of indole-3-carbaldehyde with aryl amines in refluxing dioxane. Under the above mentioned conditions, reasonable yields of the desired products with different substituents on the quinoline ring were obtained. (C) 2011 Elsevier B.V. All rights reserved.