Iodine‐Mediated [2+2+1+1] Annulation Using N , N ‐Dimethylformamide as a One‐Carbon Synthon: Access to Pyridine and Triazine Scaffolds

A metal‐free approach to the synthesis of pyridine and 1,3,5‐triazine derivatives is attempted under the influence of molecular iodine, utilizing a [2+2+1+1] annulation strategy. This annulation strategy operates effectively with N , N‐ dimethylformamide (DMF) as a C1 Source under mild reaction conditions, yielding the corresponding products in high yields ranging from 68% to 87%. A detailed mechanistic proposal is presented and supported by density functional theory calculations, which corroborate key intermediates and the iodine‐mediated C1‐incorporation pathway.