A novel one-pot Fischerindole synthesis approach has been developed by using Bronsted acidic ionic liquids as dual solvent-catalysts. Yields of 83–97 % were obtained after reaction in BMImHSO4 at 70–110 °C in 0.5–6 h, and exclusive formation of 2,3-disubstituted indoles was observed in the reaction of alkyl methyl unsymmetrical ketones. The indoles produced could be conveniently separated from the
An Electrophilic Bromine Redox Catalysis for the Synthesis of Indole Alkaloid Building Blocks by Selective Aliphatic C−H Amination
作者:Julien Bergès、Belén García、Kilian Muñiz
DOI:10.1002/anie.201808939
日期:2018.11.26
A new homogeneous bromine(−I/I) redox catalysis is described, which is based on monomeric bromine(I) compounds containing transferable phthalimidato groups. These catalysts enable intermolecular C−H amination reactions at previously unaccessible aliphatic positions and thus enlarge the synthetic potential of direct C−N bond formation, including its application in the synthesis of alkaloid building
Synthesis and reactions of 4-hydroxy-8,9,10,11- tetrahydropyrido[3,2,1-jk]carbazol-6-ones
作者:Wolfgang Stadlbauer、Hoai Van Dang、Birgit S. Berger
DOI:10.1002/jhet.325
日期:——
substituent in 11 gave 5‐azido‐ and 5‐amino products 12, 14 or 16. Reactions at the aromatic ring were not observed. Chlorination of 4‐hydroxypyridocarbazoles 6 with phosphoryl chloride by nucleophilic substitution took place exclusively at the 4‐position and gave 4‐chloropyridocarbazolones 17, which were further reacted to azides and amines 18, 19. J. Heterocyclic Chem., (2010).
四氢咔唑4从苯肼和环己酮得到的,得到由环缩合与2-取代的丙二酸酯5在所有情况下的4-羟基-8,9,10,11-四氢吡啶并[3,2,1- JK ]咔唑-6-酮6通过在攻击四氢咔唑4的氮和芳环; 环化的方向不取决于芳环或饱和环中的取代基。不能分离出异构的吡啶并咔唑。pyridocarbazoles的电子取代6温和的条件下发生在仅仅5位,并给pyridocarbazolediones 9,10,11含5-硝基,5-羟基或5-氯取代基。在氯取代基的交换11,得到5-叠氮基和5-氨基制品12,14或16。没有观察到在芳环上的反应。4- hydroxypyridocarbazoles氯化6与通过亲核取代磷酰氯发生只在4位和得到4- chloropyridocarbazolones 17,将其进一步反应的叠氮化物和胺18,19。J.杂环化学。(2010)。
Bismuth Nitrate Promoted Fischer Indole Synthesis: A Simple and Convenient Approach for the Synthesis of Alkyl Indoles
A novel one-pot fisher indole synthesis approach has been developed by using bismuth nitrate as a catalyst. Yields around 90-95% were obtained after reaction in methanol at reflux temperature in 20-40 min. Apart from the mild reaction conditions of the process and its excellent results, the simplicity of product isolation and the possibility to recycle the bismuth nitrate offers a significant advantage.
Unambiguous characterisation of dienylimines as intermediates in Fischer indolisation of o-substituted N-trifluoroacetyl enehydrazines
作者:Okiko Miyata、Yasuo Kimura、Takeaki Naito
DOI:10.1039/a907539i
日期:——
Thermal cyclisation of o-substituted N-trifluoroacetyl enehydrazines was systematically investigated and found to proceed via dienylimine intermediates, which were unambiguously characterised by X-ray and spectral analysis.