Accessing Borazine Substitution Patterns through Late-Stage Iodination

We have defined a procedure for the late-stage functionalization of aryl borazines to facilitate the synthesis of a diverse array of borazine derivatives with varying substitution patterns, paving the way for further exploration of the field. More in detail, we have studied and disclosed a simple iodination procedure that could be applied to several differently substituted substrates (1 a–i) with mostly good to excellent yields (47–96%). The representative iodinated compounds 2 b and 2 e, were utilized to test their use in further representative functionalization steps such as cyanation, Heck, and Sonogashira reactions. All products 3 a–e were obtained in satisfactory good to very good yields considering the multiple (three or six times) concomitant reactions.