Trifluoroacetic acid → HCID 67401210, compound

To a solution of tert-butyl (3aS)-1,1-dioxo-2,3,3a,4,6,7-hexahydroisothiazolo[2,3-a]pyrazine-5-carboxylate (360 mg, 1.303 mmol) in DCM (5 mL) at 0° C. was added TFA (1.25 mL, 16.22 mmol) dropwise and the reaction was stirred and warmed slowly to ambient temperature over 45 mins. The reaction mixture was concentrated in vacuo and the residue was adsorbed onto a pre-wetted (methanol/DCM (1:1), 10 mL) SCX-2 cartridge (10 g) and flushed with DCM/methanol (1:1, 50 mL) and then the basic components eluted with 2 M ammonia in methanol (50 mL). The basic eluent was evaporated to dryness to afford (S)-hexahydro-2H-isothiazolo[2,3-a]pyrazine 1,1-dioxide as a colourless oil (192 mg, 84%).

1. concentrationThe reaction mixture was concentrated in vacuo
2. customflushed with DCM/methanol (1:1, 50 mL)
3. washthe basic components eluted with 2 M ammonia in methanol (50 mL)
4. customThe basic eluent was evaporated to dryness

ORD record

ord-ab749352ee094acd9093481697445b8b

Source dataset

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09340546B2