Process for preparing (2z)-2-(phenylimino)-1,3-thiazolidine-4-one-sulfoxide derivatives in an enantiomerically enriched form

A Process for preparing a 2-(phenylimino)-1,3-thiazolidin-4-one sulfoxide derivative of formula (I) in enantiomerically pure or enantiomerically enriched form,

• in which
• Y1 and Y2 are each independently fluorine, chlorine or hydrogen,
• R1 and R2 are each independently hydrogen, (C1-C12)alkyl, (C1-C12)haloalkyl, cyano, halogen or nitro, and
• R3 is hydrogen or optionally substituted C6-C10-aryl, (C1-C12)alkyl or (C1-C12)haloalkyl,
• wherein the substituents are selected from halogen, (C1-C6)alkyl, (C3-C10)cycloalkyl, cyano, nitro, hydroxy, (C1-C6)alkoxy, (C1-C6)haloalkyl and (C1-C6)haloalkoxy, optionally from fluorine, chlorine, (C1-C3)alkyl, (C3-C6)cycloalkyl, cyclopropyl, cyano, (C1-C3)alkoxy, (C1-C3)haloalkyl and (C1-C3)haloalkoxy,
• comprising reacting a sulfide of formula (II)
• in which Y1, Y2, R1, R2 and R3 are as defined above,
• in the presence of an enantiomerically enriched chiral catalyst, an additive which is the salt of an organic acid and an oxidizing agent.