41018-94-4Relevant academic research and scientific papers
Synthesis of indolo[2,1-: A] isoquinoline derivatives via visible-light-induced radical cascade cyclization reactions
Wei, Yun-Long,Chen, Jian-Qiang,Sun, Bo,Xu, Peng-Fei
supporting information, p. 5922 - 5925 (2019/05/27)
We describe a photocatalyzed transformation for the synthesis of the indolo[2,1-a]isoquinoline core structure. This redox neutral reaction features mild reaction conditions and exceptional functional group tolerance. A series of valuable indolo[2,1-a]isoquinoline derivatives bearing various functional groups were synthesized using this method in good to excellent yields.
Metal-Free Visible-Light Promoted Radical Cyclization to Access Perfluoroalkyl-Substituted Benzimidazo[2,1-a]isoquinolin-6(5H)-ones and Indolo[2,1-a]isoquinolin-6(5H)-ones
Zeng, Fan-Lin,Sun, Kai,Chen, Xiao-Lan,Yuan, Xiao-Ya,He, Shuai-Qi,Liu, Yan,Peng, Yu-Yu,Qu, Ling-Bo,Lv, Qi-Yan,Yu, Bing
supporting information, p. 5176 - 5181 (2019/11/11)
A metal-free visible-light-induced cyclization procedure was developed for the rapid synthesis of perfluoroalkyl-substituted benzimidazo[2,1-a]isoquinolin-6(5H)-ones and perfluoroalkyl-substituted indolo[2,1-a]isoquinolin-6(5H)-ones under mild reaction conditions. In this procedure, the formation of electron-donor-acceptor (EDA) complex is critical for the visible-light promoted process to avoid the utilization of external photocatalysts. (Figure presented.).
Catalytic Asymmetric N-Alkylation of Indoles and Carbazoles through 1,6-Conjugate Addition of Aza-para-quinone Methides
Chen, Min,Sun, Jianwei
supporting information, p. 4583 - 4587 (2017/04/11)
Catalytic asymmetric N-alkylation of indoles and carbazoles represents a family of important but underdeveloped reactions. Herein, we describe a new organocatalytic strategy in which in situ generated aza-para-quinone methides are employed as the alkylating reagent. With the proper choice of a chiral phosphoric acid and an N-protective group, the intermolecular C?N bond formation with various indole and carbazole nucleophiles proceeded efficiently under mild conditions with excellent enantioselectivity and functional-group compatibility. Control experiments and kinetic studies provided important insight into the reaction mechanism.
Regioselective synthesis of indoles via rhodium-catalyzed C-H activation directed by an in-situ generated redox-neutral group
Muralirajan, Krishnamoorthy,Cheng, Chien-Hong
supporting information, p. 1571 - 1576 (2014/06/09)
A regioselective synthesis of indoles from arylhydrazine hydrochlorides with alkynes and diethyl ketone catalyzed by a rhodium complex is described. A possible mechanism involving an in-situ generated oxidizing directing group -N-Ni'CR1R2 assisted ortho-C-H activation and reductive elimination are proposed. The catalytic reaction is highly compatible with a wide range of functional arylhydrazines and alkynes. The reaction proceeds under mild reaction conditions and is atom-step economical.
General and efficient synthesis of indoles through triazene-directed c-h annulation
Wang, Chengming,Sun, Huan,Fang, Yan,Huang, Yong
supporting information, p. 5795 - 5798 (2013/06/27)
Unprotected indoles are prepared with the title method, which has a wide scope for alkynes. Excellent regioselectivity was accomplished for aryl-alkyl and alkyl-alkyl disubstituted acetylenes. This reaction features an unusual 1,2 rhodium migration and ring-contraction-triggered N-N bond cleavage. It allows rapid conversion of the reaction products into several functional molecules. Copyright
One-pot-one-step, microwave-assisted Fischer indole synthesis
Creencia, Evelyn Cuevas,Tsukamoto, Masayuki,Horaguchi, Takaaki
experimental part, p. 1095 - 1102 (2011/11/04)
The Fischer indole synthesis was carried out using microwaves instead of conventional heating procedures. When the mixture of phenylhydrazine, cyclohexanone and zinc chloride was irradiated at 600 W for 3 min, 76% of 1,2,3,4-tetrahydrocarbazole was obtained. However, when zinc chloride was replaced with p-toluenesulfonic acid (p-TSA), the reaction yielded 91% of 1,2,3,4-tetrahydrocarbazole. Thus, a series of indoles were prepared using microwaves in the presence of p-TSA catalyst.
A rapid and reliable assay for regioselectivity using fluorescence spectroscopy
Angelovski, Goran,Keraenen, Mark D.,Linnepe, Petra,Grudzielanek, Stefan,Eilbracht, Peter
, p. 1193 - 1199 (2007/10/03)
The first report of a fluorescence-based assay for the direct measurement of the regioselectivity of a reaction is described herein, developed from the desire to construct a quicker analytical method for the determination of the ratio of regioisomers obtained in the tandem hydroformylation/Fischer indole synthesis. The method allows for extremely rapid acquisition times, as the use of crude reaction mixtures is allowed. The assay is also shown to be overall very reliable, tolerating the presence of various functional groups and proceeding on average with a standard error of measurement comparable to that of NMR. As fluorescence is the only requirement for the employment of this analytical method, countless numbers of target-specific assays can undoubtedly be developed based upon this initial finding.
Fischer indole synthesis in the absence of a solvent
Matsumoto, Kiyoshi,Tanaka, Akinori,Yukio, Ikemi,Hayashi, Naoto,Toda, Mitsuo,Bulman, Robert A.
, p. 9 - 12 (2007/10/03)
The traditional Fischer synthesis of indoles has been investigated and it has been shown that the reaction proceeds in good yield in the absence of a solvent.
