An efficient potassium cyanide-promoted synthesis of 2-arylbenzoxazoles from [4.3.0]boron heterobicycles

The 2-arylbenzoxazoles 3a–f were produced in moderate to excellent yields merely by stirring a potassium cyanide (3 equiv)-containing methanol solution of the borobicyclic compounds 1a–f at room temperature. These compounds were fully characterized spectroscopically [IR, 1H, and 13C NMR and X-ray analysis (3a)] and by elemental analysis.