reactive partners in intramolecular inverse-electron-demand [4πs + 2πs] reactions with alkynes, they can be activated under mild and practical conditions, leading to fusednitrogen-containingheterocycles. We report an optimized synthesis of a 5-iodo-7-azaindazole by a one-pot Diels–Alder cascade that starts from a pyrimidine substituted at the 2-position by an (alkynyl)hydrazone. The safety of the process