3-Acylindoles Synthesis: Ruthenium-Catalyzed Carbonylative Coupling of Indoles and Aryl Iodides

Abstract

A novel and convenient procedure for the synthesis of 3-acylindoles from simple indoles and aryl iodides has been established. Through ruthenium-catalyzed carbonylative C-H functionalization of indoles, with Mo(CO) as the solid CO source, the desired indol-3-yl aryl ketones were isolated in moderate to good yields. Not only N-alkylindoles but also N-H indoles can be applied here.

From 3-Acyl-2-methylindoles to γ-Carbolines: Li-Promoted Cycloaddition Reaction and Its Quantum Chemical Study

“…Benzoylation of 2-methylindole 12 leads to 3-benzoyl-2-methylindole 13 . Its further methylation gives indole 14a . The technique for aminomethylation of compound 13 resulting in indoles 14b – d was elaborated in the present work (see the Experimental Section).…”

“…Spectral characteristics are the same as described. 36 General Procedure for the Synthesis of N-Aminomethylindoles 14b−d. The mixture of (2-methyl-1H-indol-3-yl)(phenyl)methanone 13, paraformaldehyde, and secondary amine (equivalent ratios of 1:2:1 respectively) was refluxed for 30 h. A completion of the reaction was determined by TLC.…”

5-Bromo-norborn-2-en-7-one derivatives as a carbon monoxide source for palladium catalyzed carbonylation reactions

“…Recent literature has shown only a few examples of cannabimimetic indoles that have been synthesised via carbonylation reactions. [29][30][31] The most relevant to this work involved a tandem C-H bond iodination and carbonylative Suzuki-Miyaura crosscoupling. 32 However, their process used gaseous CO and additives such as pyridine and CsF to facilitate the reaction.…”

Ruthenium-Catalyzed C–H Activations for the Synthesis of Indole Derivatives

“…Prabhu [62] selectively functionalize C-2 in the presence of highly reactive C-3 in indole derivatives using [Ru(p-cymene)Cl 2 ] 2 catalyst, with a conjugate addition product instead of Heck-type product or C3 substitution achieved (Scheme 36). Wu [63] developed a Ru-catalyzed carbonylative coupling of indoles and aryl iodides for the synthesis of 3-acylindoles. However, no desired products were detected when indole or 3-methyl-1H-indole was used as the substrate, indicating that the C2 methyl group of indoles played a crucial role in this C−H activation reaction.…”