Expedient Base-Mediated Desulfitative Dimethylamination, Oxidation, or Etherification of 2-(Methylsulfanyl)-3,5-dihydro-4H-imidazol-4-one Scaffolds

Abstract

The dimethylamino functionality is generally introduced onto the 3,5-dihydro-4H-imidazol-4-one skeleton by treatment of a halogenated derivative with low-boiling dimethylamine at a high temperature and pressure. The corresponding aliphatic ethers are usually prepared by Williamson ether synthesis, but the available transition-metal-catalyzed methods require highly toxic reagents (such as dimethyl sulfate or methyl halides) and expensive metal catalysts, and they entail harsh reaction conditions and complex workups. A simple and efficient method is described for base-mediated­ desulfitative dimethylamination, oxidation, or etherification at the C2-position of the 2-(methylsulfanyl)-3,5-dihydro-4H-imidazol-4-one scaffold by using potassium carbonate and aqueous N,N-dimethylformamide or an aliphatic alcohol.