Methylation of Quinazolin-4-One with "Soft" and "Hard" Methylating Agents

For the first time methylation of qinazolin-4-оne by “soft” and “hard” alkylation agents (methyl iodide, dimethylsulfate, methyltosylate) in proton polar ethanol, aproton аpolar, aproton dipolar solvents (dioxane-1,4, acetonitrile, dimethyl formamide, dimethyl sulfoxide) was studied. It was shown, that the reaction goes in two directions on atom nitrogen N-3 and oxygen O-4. It is find, that N-3/O-4 relation depends on nature of methylation agents, solvent and temperature.