Synthesis of [a]annulated carbazoles from indol-2,3-dione
摘要:
Reaction of ethyl chloroformate with 3-aroylmethylindol-2(3H)-ones 5 affords the ethyl 3-[(2-aryl-2-ethoxycarbonyloxy)ethenyl]-2-(ethoxycarbonyloxy)indole-1-carboxylates 6 from which the corresponding [a]annulated carbazoles 10 are obtained via 6pi-electrocyclization.
Synthesis of functionalized 2-oxindoles by Friedel–Crafts reactions
作者:Makafui Gasonoo、Douglas A. Klumpp
DOI:10.1016/j.tetlet.2015.06.028
日期:2015.8
The product aryl-substituted 2-oxindoles are formed in generally good yields. With substituted arenes such as toluene, bromobenzene, or anisole, the Friedel–Crafts reactions occur with excellent regioselectivity. A mechanism is proposed involving carbocationic electrophiles leading to the aromatic substitutionchemistry.
In the presence of molecular sieve (MS) 4 Å in DMF, a catalyst-free aldol condensation of a variety of aromatic and aliphatic ketones with isatins under mild reaction conditions has been developed. This approach may provide access to a wide range of 3-substituted-3-hydroxyindolin-2-ones in good to excellent yields.
Potential anticonvulsants. V. The condensation of isatins with<i>C</i>-acetyl heterocyclic compounds
作者:F. D. Popp
DOI:10.1002/jhet.5570190327
日期:1982.5
A number of C-acetyl heterocyclic compounds were condensed with isatin and substituted isatins to give a series of 3-hydroxy-3-substituted oxindoles. The products from 2-acetylfuran and isatin, 2-acetylthiophene and isatin, and 2-acetylpyridine and 1-methylisatin were active at 100 mg/Kg in the maximal electroshock seizure test.
“On water” catalytic aldol reaction catalyzed by polyetheramine (D230) has been developed for easy access to 3-substituted 3-hydroxyindolin-2-ones through the reaction between various substituted isatins and acetophenones/cyclic ketones in high yields under room temperature. Systematic mechanism investigation uncovers the secret for the on water catalytic aldol reaction: comparison of the heterogeneous
已经开发了通过聚醚胺(D230)催化的“水上”催化醛醇缩合反应,可通过在室温下高产率地使各种取代的靛红与乙酰苯/环酮之间的反应轻松获得3-取代的3-羟基吲哚-2-酮。系统的机理研究揭示了水催化醛醇缩合反应的奥秘:比较异构反应和均相反应的情况,产率分别为95%和20%,表明水上反应占主导。当将水添加到CDCl 3中时,基于C2和C3的13 C NMR信号的下场位移,测试了isatin与H 2 O之间的界面氢键靛红溶液;路易斯碱聚醚胺D230通过烯胺机制催化醛醇缩醛反应,该机制已通过原位NMR和ESI-MS分析验证。