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The Cover Feature shows the synthesis of substituted indolo[1,2‐a]quinoline‐5(6H)‐ones starting from 1‐(2‐ethynylphenyl)‐1H‐indoles and N‐oxides by a gold‐catalyzed oxidation of the triple bond, followed by an acid‐promoted intramolecular cyclization at the indole C‐2 position. More information can be found in the Research Article by E. Brambilla, V. Pirovano and co‐workers (DOI: 10.1002/ejoc.202400083). Cover design by Dominica Del Grosso...By Elisa Brambilla; Mariaclara Gugiatti; Silvia Rizzato; Giorgio Abbiati and Valentina PirovanoReported by Author; Author; Author; Author; Author [Extracted from the article]

The reactivity of vinyl‐/furoindole derivatives with gold‐activated π‐systems is the subject of extensive investigation. In the presence of these electrophilic partners, the realized transformations allow for the construction of different and fascinating architectures via cycloaddition and cyclization reactions often included in cascade processes. The reactions realized involving in these processes an external substituent at the indole moiety are the subject of the present minireview. [ABSTRACT FROM AUTHOR]

The gold-catalyzed synthesis of tetrahydrocarbazoles through dearomative [4+2] cycloaddition reactions of 3/2-substituted 2/3-vinylindoles with allenamides is reported. In particular, we optimized the enantioselective variant of these cycloadditions. Using allenamides as dienophiles 3-substituted 2-vinylindoles gave the corresponding carbazoles with high chemo-, regio- and enantioselectivity. Good results were obtained also with 2-methyl 3-vinylindoles even if mixtures of ( Z) and ( E) isomers were isolated in high er and in excellent overall yields. [ABSTRACT FROM AUTHOR]

The gold-catalyzed intermolecular Diels-Alder cycloaddition and competitive Michael addition reactions between 2-vinylindoles and enones/enals are reported. The reaction outcome strictly correlates with the electronic character of the heteroaromatic substrate. Thus, Diels-Alder cycloadducts are the sole products in the presence of less electron-rich heterocycles, whereas Michael addition adducts are observed with more electron-rich heterocycles. Plausible competitive reaction mechanisms are proposed and discussed as well. [ABSTRACT FROM AUTHOR]

Abstract: A novel InCl3-mediated one-pot reaction leading to 1-aminocarbazoles is reported. Starting from easily available 2-acetyl-1H-indole, the reaction involves the alkylation of C-3 with a prop-2-yn-1-ol followed by a domino aminobenzannulation reaction in the presence of a secondary amine. The indium salt is most likely involved as catalyst in all three steps of the one-pot reaction. Starting from 2-acetyl-1H-indole and a series of prop-2-yn-1-ols and secondary amines a small library of products has been obtained. [Copyright &y& Elsevier]

Starting from simple indole, a straightforward and inexpensive four-step synthetic approach to indeno[2,1- b ]indol-6-one nucleus is described. [ABSTRACT FROM AUTHOR]

The synthesis of the pyrazino[1,2-α]indole nucleus was achieved by intramolecular cyclization of several 2-carbonyl-1-propargylindoles in the presence of ammonia. The reaction conditions were optimized using microwave heating and a pool of catalysts. Cyclization of 1-alkynylindole-2-carbaldehydes was easily accomplished under standard heating conditions, whereas microwave heating contributed to reduced reaction times and improved overall yields. Moreover, a fine-tuning of the microwave irradiation time made possible the selective synthesis of both pyrazino[1,2-α]-indole isomers. TiCl4 proved the catalytic system of choice to achieve pyrazinoindoles in satisfactory yields starting from 1-alkynyl-2-acetylindoles and 1-alkynyl-2-benzoylindole derivatives. Also in these cases, microwave heating contributed to faster reactions and improved yields. The uncatalyzed versus catalyzed reaction mechanism is discussed. [ABSTRACT FROM AUTHOR]

Indole 2-carboxamide derivatives 4 underwent palladium-catalyzed intramolecular cyclization reactions to afford β-carbolinones or pyrazino [1,2-a]indoles according to different reaction pathways. The complete regioselectivity of the reactions was obtained in different reaction conditions. [ABSTRACT FROM AUTHOR]