One-Pot Synthesis of Substituted Benzoxazoles Using Aminophenols and -Diazoesters via Annulation of Amide Intermediate Using Co₂(CO)₈ as a Solid Carbonyl Source

Synthesis of benzoxazoles via amide formation from amino phenols and alpha-diazoesters using dicobalt octacarbonyl as a solid CO source is reported. Our methodology provides a strategy for synthesizing substituted benzoxazoles with methylene linker between the benzoxazole and aromatic ring systems. Substrates with different substituents were employed to produce corresponding benzoxazoles. The synthesized compounds were characterized by using standard spectroscopic and analytical techniques including single crystal XRD studies.