Azide-free cyclization reaction access to 4-aryl-NH-1,2,3-triazoles: P-toluenesulfonyl hydrazide and sulfamic acid as nitrogen sources

A molecular-iodine mediated azide-free multicomponent cyclization reaction leading to NH -1,2,3-triazoles from acetophenones, p -toluenesulfonyl hydrazide, and sulfamic acid. This reaction offers a safe metal- and azide-free strategy to triazoles.