A direct access to isoxazoles from ynones using trimethylsilyl azide as amino surrogate under metal/catalyst free conditions

A general method for isoxazoles from readily available ynones using trimethylsilyl azide as an amino surrogate, likely via an unprecedented hydroazidation of the alkyne and denitrogenative cyclization, is demonstrated. The method neither required any catalyst nor demanded unusual conditions to afford the products with outstanding functional group compatibility.