Base‐Controlled Selectivity in the Synthesis of Linear and Angular Fused Quinazolinones by a Palladium‐Catalyzed Carbonylation/Nucleophilic Aromatic Substitution Sequence

Abstract

A new approach for the facile synthesis of fused quinazolinone scaffolds through a palladium-catalyzed carbonylative coupling followed by an intramolecular nucleophilic aromatic substitution is described. The base serves as the key modulator: Whereas DBU gives rise to the linear isomers, Et 3 N promotes the preferential formation of angular products. Interestingly, a light-induced 4+4 reaction of the product was also observed.

Copper‐mediated annulation of 2‐aminoacetophenones and 2‐bromopyridines

“…A seminal example was reported by Beller and Wu that described a rare palladium-catalyzed carbonylative coupling of 2-aminopyridines, 2-bromobenzenes, and carbon monoxide to afford quinazolinones. [3] Anthranilic acids could be competent substrates. [4] Directed carbonylation of ortho C-H bonds in N- (2pyridinyl)anilines or 8-aminoquinoline amides have been recently developed.…”

Electrochemical Umpolung of Bromide: Transition-Metal-Free Bromination of Indole C–H Bond

“…Aromatic bromides are an important class of compounds, which are commonly utilized as the coupling partner in transition-metal-catalyzed cross-coupling reactions [ 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 ]. Thus, the development of a synthetic method of arylbromides has attracted tremendous efforts [ 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 ].…”