1,2‐Bis‐Triazenylarenes Enable Vicinal Sandmeyer‐Type Reactions

The introduction of two nucleophiles in the vicinal position of arenes via Sandmeyer-type reactions is compromised by the problematic diazotization of ortho-diaminoarenes. Herein, it is shown that vicinal substitution reactions are facilitated by the use of 1,2-bis-triazenylarenes. Two distinct methodologies for the synthesis of these triazenes are presented. The first approach involves the sequential conversion of 1-amino-2-iodoarenes into first mono- and then bis-triazenylarenes. The second procedure is based on Ru-catalyzed [2 + 2 + 2] cycloaddition reactions between diynes and a 1,2-bis-triazenylalkyne. The two triazene groups in the products can be substituted sequentially by a range of nucleophiles including fluoride, chloride, bromide, iodide, azide, hydroxide, methoxide, and acetamide.