Controlled Dimroth Rearrangement in the Suzuki–Miyaura Cross Coupling of Triazolopyridopyrimidines

Polynitrogen heterocycles are often subject to Dimroth rearrangement which consists of ring opening, bond rotation, and ring closure. In this note, we report a synthesis of two new families of triazolopyridopyrimidines. Successful functionalization via a Suzuki–Miyaura coupling was performed with total control of triazole (Dimroth) isomerization based on the judicious choice of reaction conditions.