Sodium Hydroxide → HCID 53248042, compound

Temperature

75 °C

To a solution of 4-(pyridin-2-yldisulfanyl)butanoic acid (725 mg, 3.16 mmol) and 1,2-di(pyridin-2-yl)disulfane (700 mg, 3.18 mmol) in 15 ml of DCE (1,2-dichloroethane) at 75° C. was added chlorosulfuric acid (300 μL, 4.51 mmol). After stirring for 20 min at 75° C., another portion of chlorosulfuric acid (300 μL, 4.51 mmol) was added. The mixture was allowed to stir at 75° C. for 20 min, then another portion of chlorosulfuric acid (200 μL, 3.0 mmol) was added. Again 25 min later, the final portion of chlorosulfuric acid (200 μL, 3.0 mmol) was added and the mixture was stirred for further 25 min. The mixture was immediately cooled on ice bath, neutralized with 1M NaOH to pH ˜7, diluted with EtOAc/Hexane (1:1), separated, and the organic layer was washed with pure water (3×25 ml) while the generated each of aqueous layer was washed with EtOAc/Hexane (1:1, 35 ml). The aqueous layers were combined, acidified with HCl/HOAc to pH 3˜4, concentrated to ˜10 ml, diluted with MeCN (100 ml), sonicated (or quickly stirred) for 1 h, filtered, and the resulting pellet washed with water/MeCN (1:10). The solution was then concentrated and purified on a Si02 cartridge (40 g) eluting with water/MeCN/HOAc (1:10:0.01). To the pooled fractions containing the product, DMF (˜5 ml) was added and evaporated to dryness to afford 4-(pyridin-2-yldisulfanyl)-2-sulfobutanoic acid (295 mg, 0.954 mmol, 30.2% yield).

1. stirringto stir at 75° C. for 20 min
2. stirringthe mixture was stirred for further 25 min
3. temperatureThe mixture was immediately cooled on ice bath
4. customseparated
5. washthe organic layer was washed with pure water (3×25 ml) while the
6. washwas washed with EtOAc/Hexane (1:1, 35 ml)
7. concentrationconcentrated to ˜10 ml
8. additiondiluted with MeCN (100 ml)
9. customsonicated (or
10. stirringquickly stirred) for 1 h
11. filtrationfiltered
12. washthe resulting pellet washed with water/MeCN (1:10)
13. concentrationThe solution was then concentrated
14. custompurified on a Si02 cartridge (40 g)
15. washeluting with water/MeCN/HOAc (1:10:0.01)
16. additionTo the pooled fractions containing the product, DMF (˜5 ml)
17. additionwas added
18. customevaporated to dryness

ORD record

ord-b9e58159a3e84e018de8f478ea3db0d9

Source dataset

uspto-grants-2016_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09242936B2