1,4-Dibromobutane → 6-chloro-3,4-dihydro-2-(4-bromobutyl)-2H-thieno[3,2-e]-1,2-thiazine-4-ol 1,1-dioxide

A solution 6-chloro-3,4-dihydro-2H-thieno[3,2-e]-1,2-thiazine-4-ol 1,1-dioxide (9.0 g, 37.6 mmol) in dimethylformamide (200 mL, anhydrous) and sodium hydride (60% in oil, 1.66 g, 41.5 mmol) was reacted with 1,4-dibromobutane at 0°. The reaction was stirred in an ice bath for 30 min and then it was allowed to warm to room temperature and stir for three days. The mixture was poured into ice water (400 mL) and extracted with diethyl ether (2×200 mL). The combined organic layers were washed with water (200 mL), brine (200 mL) and then were dried over magnesium sulfate and evaporated. The resulting residue was purified by silica gel flash chromatography with hexane/ethyl acetate (7:3) to give 6-chloro-3,4-dihydro-2-(4-bromobutyl)-2H-thieno[3,2-e]-1,2-thiazine-4-ol 1,1-dioxide as a colorless oil (10.62 g, 75%); the 1H NMR was consistent with the structure.

1. stirringstir for three days
2. extractionextracted with diethyl ether (2×200 mL)
3. washThe combined organic layers were washed with water (200 mL), brine (200 mL)
4. dry with materialwere dried over magnesium sulfate
5. customevaporated
6. customThe resulting residue was purified by silica gel flash chromatography with hexane/ethyl acetate (7:3)

ORD record

ord-e9e7032d862e4bd3932ea3db3420c39b

Source dataset

uspto-grants-2007_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07285553B2