Application of Vitreoscilla Hemoglobin as a Green and Efficient Biocatalyst for the Synthesis of Benzoxazoles in Water

Abstract

We report an efficient and eco‐friendly method for the Vitreoscilla hemoglobin (VHb)‐catalysed synthesis of benzoxazoles in water at room temperature. tert‐Butyl hydroperoxide and 2,2,6,6‐tetramethyl‐1‐piperidinyloxy were used as oxidant and radical scavenger, respectively. A total of 27 functionally diverse benzoxazoles were prepared in moderate to high yields (62%‐94%) by the annulation reaction of phenols with amines in the presence of VHb in 1 hour. Thus, this method is highly viable for practical applications. This work broadens the application of hemoglobin to organic synthesis.