Synthesis of Bis(indolyl)methanes via thiourea organocatalysts carrying 3,5-bis(trifluoromethyl)phenyl or 3,5-dichlorophenyl moieties

• Published in: Journal of molecular structure 2022-09, Vol.1264, p.133209, Article 133209
• Main Authors: Rivas-Loaiza, J. Antonio, García-Merinos, J. Pablo, Ramírez-Díaz, Martha I., López-Ruiz, Heraclio, López, Yliana
• Format: Article
• Language: English
• Subjects: BIMs; Imines; Indole; Organocatalysis; Thiourea
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2022.133209

•Six thiourea organocatalysts were used for the synthesis of bis(3-indolyl)methanes.•Thiourea organocatalys provided better conversion for the aldehydes under microwave.•The most active organocatalyst for aldehydes and imines were thiourea 3 and 6.•These methods provide an alternative to obtain BIMs under fast and mild conditions.•Compounds 3, 5, 9, 10 and 13 showed inhibitory antibacterial activity. Bis(indolyl)methane derivatives (BIMs) were synthesized in moderate to good yields by electrophilic aromatic substitution of indole (27) with various aldehydes or imines in the presence of thiourea organocatalysts carrying 3,5-bis(trifluoromethyl)phenyl or 3,5-dichlorophenyl moieties. Reactions were performed under conventional and microwave (MW) irradiation without solvent. The most active organocatalyst for aldehydes was thiourea 3 and for imines, the thiourea 6. For compound 11 derived from 2,4,6-trimethoxybenzaldehyde (30) its structure was confirmed by X-ray analysis. Furthermore, some of the synthesized compounds were evaluated for their effectiveness as antibacterials. Compounds 3, 9, 10 and 13 showed inhibitory activity against Gram positive bacteria whereas compound 5 showed inhibitory activity against Gram positive and Gram negative bacteria. [Display omitted] .