Copper‐Catalyzed Aerobic Oxidation of N‐Pyridylindole Leading to Fused Quinazolinones

Abstract

Copper catalyzed aerobic oxidation enables the tandem selective and efficient transformation of N‐pyridylindole for the construction of 11H‐pyrido[2,1‐b]quinazolin‐11‐ones. The reaction shows good efficiency to accomplish the aerobic oxidation. Mechanistic investigation indicated the facile oxidation of N‐pyridylindole underwent the single‐electron‐transfer oxidation, the capture of molecular oxygen and the extrusion of carbon monoxide to deliver the desired 11H‐pyrido[2,1‐b]quinazolin‐11‐ones.

Copper dual-atom catalyst mediated C3–H amination of indoles at room temperature

“…1 Due to their extensive applications, the functionalization of indoles has long been an attractive topic in synthetic chemistry. 2 Organic compounds containing aryl C–N moieties are ubiquitous in functional materials and natural products. As such, direct C–H amination has emerged as an attractive approach to synthesize these compounds, characterized by several appealing features, such as high atom economy, high step economy and synthetic practicality.…”

Recent advances in the synthesis of 2,3-fused quinazolinones

“…It is worth noting that the electron-withdrawing group (CF 3 ) could still afford the corresponding product 34e in 50% yield. 26 The reaction was performed with 20 mol% of Cu(OAc) 2 , 30 mol% of imidazole 36 as a ligand, and 1.0 equiv. of PivOH in DMSO.…”

“…In 2020, Liu et al reported the copper-catalyzed aerobic oxidation of N -pyridylindole 35 to synthesize pyrido[2,3- b ]quinazolinones 37 in good yields (Scheme 18). 26 The reaction was performed with 20 mol% of Cu(OAc) 2 , 30 mol% of imidazole 36 as a ligand, and 1.0 equiv. of PivOH in DMSO.…”

Persulfate-Promoted Carbamoylation/Cyclization of Alkenes: Synthesis of Amide-Containing Quinazolinones

“…Consequently, remarkable efforts have been devoted to their efficient synthesis in the past few years [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Traditionally, 2,3-fused quinazolin-4(3 H )-ones can be prepared through multiple pathways, such as dehydrogenative cross-coupling reactions [ 16 , 17 , 18 , 19 , 20 , 21 ], oxidative ring-opening reactions [ 22 , 23 , 24 , 25 , 26 , 27 , 28 ], cycloaddition reactions [ 29 , 30 , 31 , 32 ], etc. However, these methods suffer from the use of complicated starting materials, harsh reaction conditions, and complex reaction procedures.…”