Metal-free synthesis of imidazole by BF3·Et2O promoted denitrogenative transannulation of N-sulfonyl-1,2,3-triazole

The first BF₃·Et₂O promoted metal-free denitrogenative transannulation of N-sulfonyl-1,2,3-triazole was reported, leading to the synthesis of functionalized imidazoles with a broad scope.