Reaction #79497

Reaction equation

5-Methyl-5-phenyl-3-phenylamino-2-thioxothiazolidin-4-one

methylene chloride

triethyloxonium tetrafluoroborate

hydroxylamine hydrochloride

→

2-hydroxyimino-5-methyl-5-phenyl-3-phenylaminothiazolidine-4-one

Yield 70.2%

Solvents

methanol

triethylamine

Conditions

Workup

1. 1
   workup.ADDITIONwere added at 0° C
2. 2
   workup.STIRRINGThe reaction mixture was again stirred for 2 hrs at room temperature
3. 3
   Otherfollowed by evaporation of the solvents under reduced pressure
4. 4
   workup.ADDITIONThe residue was added to ice water
5. 5
   Extractionextracted with ethyl acetate
6. 6
   DryingThe ethyl acetate solution was dried over anhydrous ethyl acetate
7. 7
   Otherthe solvent was then evaporated under reduced pressure
8. 8
   OtherThe residue was purified by column chromatography (ethyl acetate-n-hexane, ½)

Procedure

5-Methyl-5-phenyl-3-phenylamino-2-thioxothiazolidin-4-one (0.3 g) was added to a 1M methylene chloride solution of triethyloxonium tetrafluoroborate (1 ml) at room temperature with stirring. After stirring the mixture for 24 hrs hydroxylamine hydrochloride (0.1 g) and triethylamine (0.3 g) in methanol (10 ml) were added at 0° C. The reaction mixture was again stirred for 2 hrs at room temperature followed by evaporation of the solvents under reduced pressure. The residue was added to ice water and then extracted with ethyl acetate. The ethyl acetate solution was dried over anhydrous ethyl acetate and the solvent was then evaporated under reduced pressure. The residue was purified by column chromatography (ethyl acetate-n-hexane, ½) to yield 2-hydroxyimino-5-methyl-5-phenyl-3-phenylaminothiazolidine-4-one (0.21 g) having a melting point of 62-63° C.

Source