Triazenes have previously been established as versatile intermediates and linkers for conventional and solid-phase synthesis that can be considered protected diazonium salts. According to the previous work , triazenopyrazoles could serve as azide sources and thus as building blocks for synthesizing pyrazolotriazoles by CuAAC reactions. To find a feasible approach to pyrazolotriazoles of type 1 with a highly substituted scaffold, we decided to explore the benefits of a modification of the triazene-protected pyrazole core. In the next step, a cycloaddition of the gained synthesized azidopyrazoles with different alkynes was to be conducted. The 3-(3,3-diisopropyltriaz-1-en-1-yl)-1H-pyrazole precursors 15a-d were synthesized according to previously reported procedures via the generation of a diazonium salt from aminopyrazoles 14a-d followed by the addition of diisopropylamine, either in a one-pot synthesis or in two consecutive steps (Table ).Subsequently, different aliphatic and aromatic substituents were attached to the pyrazole nitrogen by nucleophilic substitution with suitable organohalides 16 and cesium carbonate. Due to the pyrazole tautomerism , the formation of two possible regioisomers, 17 and 18, was anticipated and could be confirmed experimentally. Depending on the employed halide 16, the distribution of the obtained products varied. A considerable excess of the dominating isomer with yields of up to 70% could be obtained in some cases (see 17f or 17m), whereas the isomers were isolated in a 1:1 ratio for compound 17c or 17h. A strong trend towards regioisomer 17 as the main product was observed for substituted phenyl residues, presumably due to the higher steric hindrance (see 17e-g). The results for benzylic residues differed depending on the benzylic residue's functional groups and the pyrazole substitution pattern. For starting materials 15a and 15d, an excess of product 17 was usually observed. With the ester-functionalized triazene 15c and m-substituted benzylic reagents, regioisomer 18 was the predominant product (see 18i and 18j). In total, 13 groups could be attached to the different triazenopyrazoles, yielding 18 products (see Table ). DCM failed for 4-substituted pyrazoles; the formation of the target products was only observed when 5-methyl-pyrazoles such as 15b were used. Therefore, a modified procedure was applied, heating the triazenes to 50 °C. This optimization allowed for the isolation of the corresponding azides 19a-v in yields of 57% to quantitative (Scheme 2). However, the procedure could only be used to convert isomer 17.