Synthesis of 4H‐Benzo[e][1,3]oxazin‐4‐ones by a Carbonylation–Cyclization Domino Reaction of ortho‐Halophenols and Cyanamide
نویسندگان
چکیده
A mild and convenient one-step preparation of 4H-1,3-benzoxazin-4-ones by a domino carbonylation-cyclization process is developed. Readily available ortho-iodophenols are subjected to palladium-catalyzed carbonylative coupling with Mo(CO)6 and cyanamide, followed by a spontaneous, intramolecular cyclization to afford 4H-1,3-benzoxazin-4-ones in moderate to excellent yields. Furthermore, the scope of the reaction is extended to include challenging ortho-bromophenols. Finally, to highlight the versatility of the developed method, Mo(CO)6 is successfully replaced with a wide array of CO-releasing reagents, such as oxalyl chloride, phenyl formate, 9-methylfluorene-9-carbonyl chloride, and formic acid, making this an appealing strategy for the synthesis of 4H-benzo[e][1,3]oxazin-4-ones.
منابع مشابه
Front Cover: Synthesis of 4H‐Benzo[e][1,3]oxazin‐4‐ones by a Carbonylation–Cyclization Domino Reaction of ortho‐Halophenols and Cyanamide (ChemistryOpen 5/2017)
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