Hydrochloric Acid → Isohexane ethyl acetate

A solution of the sulfinamide from Step 5 (0.78 g, 1.63 mmol) and 1M HCl in diethyl ether (4 mL) in methanol (10 mL) was stirred at rt for 25 h. The solution was poured into sat. aq. sodium hydrogencarbonate (100 mL) and extracted with ethyl acetate (2×50 mL). The extracts were washed with water (50 mL), brine (20 mL), dried over sodium sulfate and concentrated to give a gum. The material was redissolved in pyridine (10 mL) and dichloromethane (10 mL) and stirred at 0° C. 2-Chloroethanesulfonyl chloride (0.2 mL, 1.0 mmol) was added dropwise. After stirring at rt for 18 h the mixture was diluted with 1M citric acid (100 mL) and extracted with dichloromethane-methanol (9:1, 2×100 mL). The extracts were washed with water (50 mL) and brine (20 mL, dried over sodium sulfate and concentrated. Chromatography, eluting with 50% then 100% ethyl acetate-isohexane, gave the sulfonamide as a pink solid (0.349 g, 46%).

1. extractionextracted with ethyl acetate (2×50 mL)
2. washThe extracts were washed with water (50 mL), brine (20 mL)
3. dry with materialdried over sodium sulfate
4. concentrationconcentrated
5. customto give a gum
6. extractionextracted with dichloromethane-methanol (9:1, 2×100 mL)
7. washThe extracts were washed with water (50 mL) and brine (20 mL
8. dry with materialdried over sodium sulfate
9. concentrationconcentrated
10. washChromatography, eluting with 50%

ORD record

ord-9a2af6a848714def84f2591207c140a7

Source dataset

uspto-grants-2008_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07435748B2