Alkyl Ether as a One-Carbon Synthon: Route to 2,4-Disubstituted 1,3,5-Triazines via C-H Amination/C-O Cleavage under Transition-Metal-Free Conditions.

A transition-metal-free oxidative formal [3 + 2 + 1] cycloaddition for the synthesis of symmetrical and unsymmetrical 2,4-disubstituted 1,3,5-triazines has been first demonstrated. The reaction is involved in a domino C-H amination of alkyl ethers with amidines, C-O cleavage, nucleophilic addition, condensation, and an oxidative aromatization process. Notably, two C-N bonds were constructed in one pot, and alkyl ethers were employed as a novel carbon source of 1,3,5-triazines. The preliminary mechanistic studies revealed the reaction underwent a radical pathway.