Carbonylation of Anthranilic Acid with Aryl and Heteroaryl Bromides to Synthesize Benzoxazinone Derivatives

Abstract

As imple and efficient, PdCl 2 (PhCN) 2 / P(tBu) 3 ·HBF 4 -catalyzed carbonylative cyclizationo fa nthranilic acid with aryl bromide was investigatedf or the synthesis of benzoxazinones under mild reactionc onditions. The developed protocol has been extended fort he synthesis of quinazolin-4(3 H)-ones. Furthermore, the tolerance of aw ider ange of functional groups on anthranilic acid as well as on aryl bromide demonstrates the practical utility of the protocol.Scheme1.Classical and carbonylativeapproach for the synthesis of benzoxazinones.[a] S.

Pd‐Catalyzed Carbonylative Synthesis of 4H‐Benzo[d][1,3]Oxazin‐4‐Ones Using Benzene‐1,3,5‐Triyl Triformate as the CO Source

“…Since the earliest reports by the groups of Cacchi [20] and Alper [21] in 1990s, many carbonylative synthesis of benzoxazinone derivatives from N-(ortho-haloaryl)anilines or amides have been reported. [22] Recently, Pd-catalyzed carbonylative synthesis of these heterocycles from anthranilic acids, [23] N-acyl benzotriazoles, [24] 2-iodoaryl azides [25] have been developed. In addition, Pd-catalyzed oxidative C-H activation of aniline derivatives has also been reported for the synthesis of 4Hbenzo[d] [1,3]oxazin-4-ones.…”