Metal-Free Synthesis of Polysubstituted Triazoloquinoxalines Using Alkynols as the Key Building Blocks

<i>o</i>-Phenylenediamines, <i>o</i>-nitroanilines, and Boc-<i>o</i>-phenylenediamines were converted to <i>N</i>-Ts/Ns-<i>o</i>-phenylenediamines, followed by Mitsunobu alkylation with prop-2-yn-1-ols. After one-pot azidation, the resulting intermediates underwent Huisgen cycloaddition, which yielded Ts/Ns-dihydrotriazoloquinoxalines. Cleavage of the arylsulfonyl moiety provided (dihydro)triazoloquinoxalines with the possibility of modifying the <i>N</i> ⁵ position. The application of but-3-yn-1-ols and pent-4-yn-1-ols allowed the preparation of benzotriazolodiazepines and benzotriazolodiazocines. The developed protocols enable the preparation of diversely substituted products from readily available starting materials under mild and metal-free conditions.