Reactivity of 2-thiohydantoins towards various electrophilic reagents: Applications to the synthesis of new 2-ylidene-3,5-dihydro-4H-imidazol-4-ones

Abstract

A new route to 5-(imidazolidin-2-ylidene)-2-methylsulfanyl-3,5- dihydroimidazol-4-ones 4a-c using ketene dithioacetal intermediates 3a-c is described. The reactivity of thiohydantoin derivatives 2a-c towards N,N-dimethylformamide diethylacetal (DMF-DEA) was also explored using solvent-free technique under microwave irradiation (μ ω). The 1H- and 13C-NMR spectra of some representative products are discussed.