A Modular Synthesis of N-Benzotriazole Ureas Using Alkylation of 5-Nitrobenzotriazole

N-Alkylations of monosubstituted benzotriazoles yield isomeric products with distinct topology, i.e. 1H- or to 2H- isomers. Therefore, the molecular shape of these compounds varies and this results in distinct biological and physical properties. Herein, a protocol for the simple synthesis of various alkyl-aminobenzotriazoles using 5-nitrobenzotriazole is reported. This synthetic approach furnishes 2-alkyl-5-nitro-2H-benzotriazoles as major products in most of the attempted cases. All three obtained isomers were separable from each other by standard column chromatography. In addition, three alternative approaches furnishing selectively substituted alkyl-amino-1H-benzotriazoles are described. Finally, a library of sixty-eight N-benzotriazoylureas and six N-benzotriazoylthioureas was synthesized by reactions with either isocyanates (phenyl chloroformate) or isothiocyanates.