Copper-catalysed N-arylation of 5-aminopyrazoles: a simple route to pyrazolo[3, 4-b]indoles. Issue 33 (14th August 2020)

• Record Type: Journal Article
• Authors: Chatterjee, Arpita; Murmu, Chudamani; Peruncheralathan, S.
• Is Part Of: Organic & biomolecular chemistry. Volume 18:Issue 33(2020)
• Page Start: 6571
• Page End: 6581
• Publication Date: 2020-08-14
• Subjects: Chemistry, Organic -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1039/d0ob00812e
• Languages: English
• ISSNs: 1477-0520

Abstract

Abstract : Two classes of pyrazolo fused N-heterocycles are synthesized from 5-aminopyrazoles using an inexpensive and non-toxic CuCl catalyst. The N -arylation process is very selective and does not require any ligands. Abstract : A copper-catalysed intramolecular N -arylation of 5-aminopyrazoles is demonstrated for the first time. Highly substituted pyrazolo[3, 4- b ]indoles are synthesized. In particular, the indole core is decorated with halogens and alkyl and methoxy groups. Furthermore, a selective N -arylation of unsymmetrical diaryl bromide containing pyrazoles is exemplified, resulting in valuable pyrazolo[1, 5- a ]benzimidazoles.