Reaction #7407

Reaction equation

tert-butyl (2R)-2-((3S)-3-{[(6-chloro-2-naphthyl)sulfonyl]amino}-2-oxopyrrolidin-1-yl)propanoate

trifluoroacetic acid

1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride

HOBT

piperidine

→

title compound

Yield 82.0%

6-Chloro-N-{(3S)-1-[(1R)-1-methyl-2-oxo-2-piperidin-1-ylethyl]-2-oxopyrrolidin-3-yl}naphthalene-2-sulfonamide

Yield 82.0%

Solvents

DCM

triethylamine

Conditions

Workup

1. 1
   ConcentrationThe mixture was then concentrated under reduced pressure
2. 2
   Otherto give an oil which
3. 3
   workup.STIRRINGAfter stirring at room temperature for 1 h
4. 4
   workup.STIRRINGstirring
5. 5
   workup.WAITwas continued for 48 h
6. 6
   OtherThe reaction mixture was partitioned between DCM and water
7. 7
   ExtractionThe organic extract
8. 8
   Concentrationwas concentrated under reduced pressure
9. 9
   Otherthe residue purified
10. 10
    WashSPE (silica, eluting with cyclohexane:ethyl acetate 5:1, 3:1, 1:1, 1:3 and ethyl acetate)

Procedure

A solution of tert-butyl (2R)-2-((3S)-3-{[(6-chloro-2-naphthyl)sulfonyl]amino}-2-oxopyrrolidin-1-yl)propanoate (0.025 g) in DCM (3 ml) was treated with trifluoroacetic acid (3 ml) and stirred at room temperature for 2 h. The mixture was then concentrated under reduced pressure to give an oil which was subsequently treated with 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride (0.013 g), HOBT (0.009 g) and triethylamine (0.023 ml). After stirring at room temperature for 1 h, piperidine (0.007 ml) was added and stirring was continued for 48 h. The reaction mixture was partitioned between DCM and water. The organic extract was concentrated under reduced pressure and the residue purified using SPE (silica, eluting with cyclohexane:ethyl acetate 5:1, 3:1, 1:1, 1:3 and ethyl acetate) to give the title compound (0.021 g) as a colourless gum.

Source