Highly Efficient Dehydrogenation of 5-Benzyl-3-phenyl-2-thioxoimidazolidin-4-one: Microwave versus Flash Vacuum Pyrolysis Conditions

Abstract

5-Benzyl-3-phenyl-2-thioxoimidazolidin-4-one underwent thermal dehydrogenation to afford 5-benzylidene-2-thioxoimidaxolidin-4-one under microwave and flash vacuum pyrolysis conditions. A high predominance of the Z-isomer over the E-isomer of the imidazolidinone product was achieved. By using DFT and NBO calculations, the mechanism of the dehydrogenation and the selectivity were also explored.