Chiral Thiophosphorylated Thioureas: Synthesis, Structure, and Cyclization Reaction

A number of chiral racemic and enanthiopure thiophosphorylated thioureas were synthesized by the reaction of 2-aminobutan-1-ol and 1-(a-aminobenzyl)-2-naphthol with O,O-diethyl thiophosphoryl isothiocyanate. It was found that such thioureas undergo the cyclization reaction under basic conditions with hydrogen sulfide elimination and the formation of thiophosphorylated oxasines. X-Ray single crystal diffraction revealed that the structure of thiourea is close to the prereaction state of the cyclization reaction.