Parallel Strategies for the Synthesis of Annulated Pyrido3,4-bindoles via Rh(I)- and Pd(0)-Catalyzed Cyclotrimerization

• Published in: Tetrahedron letters 2018-12, Vol.59 (49), p.4311
• Main Authors: Saliba, Bianca M, Khanal, Satyam, O'Donnell, Michael A, Queenan, Kathryn E, Song, Junho, Gentile, Matthew R, Mulcahy, Seann P
• Format: Article
• Language: English
• ISSN: 0040-4039
• DOI: 10.1016/j.tetlet.2018.10.050

Two different pathways for the synthesis of annulated pyrido[3,4-b]indoles are reported using metal-catalyzed cyclotrimerization reactions. A stepwise process using Rh(I)-catalysis in the final step of the synthesis and a multicomponent, tandem catalytic approach using Pd(0)-catalysis both lead to complex nitrogen-containing heterocycles in good yields. Substituent effects are investigated for both pathways, demonstrating that the Pd(0)-catalyzed approach is more sensitive to electron- withdrawing groups.Two different pathways for the synthesis of annulated pyrido[3,4-b]indoles are reported using metal-catalyzed cyclotrimerization reactions. A stepwise process using Rh(I)-catalysis in the final step of the synthesis and a multicomponent, tandem catalytic approach using Pd(0)-catalysis both lead to complex nitrogen-containing heterocycles in good yields. Substituent effects are investigated for both pathways, demonstrating that the Pd(0)-catalyzed approach is more sensitive to electron- withdrawing groups.