PURPOSE: The hydrolysis of 2,2-dialkylthiazolidine is effected in water in the presence of a mineral acid to produce high-purity titled compound used as a radiation disorder preventive and synthetic intermediate of medicine with no formation of by-products in high yield with no use of hydrogen sulfide, a large amount of solvent and extremely low temperature.
CONSTITUTION: Readily available 2,2-dialkylthiazolidine of formula I (R1 and R2 are straight or branched chain alkyl, preferably 1W4 alkyl) and a solution of the equimolar or a little excess amount of mineral acid such as sulfuric, nitric, preferably hydrochloric or hydrobromic acid in an equivolume of water are combined and heated for 2W3hr to effect hydrolysis, resulting in the formation of titled compound of formula II (X is acid radical). The reaction is conducted generally at room temperature W100°C and the dialkyl ketone formed is expelled out of the reaction system by evaporation or distillation to accelerate the reaction.
OOSAWA YASUKO
UCHIKUGA SABUROU
