tert-Butylsulfinamide, (R)-(+)- → (R)-2-Methyl-propane-2-sulfinic acid [1-(4-bromo-2-methyl-phenyl)-ethylidene]-amide

Temperature

65 °C

Titanium(IV) ethoxide (10.7 mL) was added to a solution of 1-(4-bromo-2-methyl-phenyl)-ethanone (4.41 g) and (R)-2-methyl-2-propanesulfinamide (2.76 g) in tetrahydrofuran (45 mL). The resulting solution was heated to 65° C. and stirred at this temperature for 20 h. Then, the solution was cooled to ambient temperature and another portion of titanium(IV) ethoxide (5.4 mL) and (R)-2-methyl-2-propane-sulfinamide (1.25 g) were added. After stirring the solution at 65° C. for another 12 h, the solution was cooled to ambient temperature and poured into brine. The resulting mixture was filtered over Celite and the organic phase of the filtrate was separated. The aqueous phase of the filtrate was extracted with ethyl acetate and the extracts were combined with the separated organic phase. The combined organic phases were washed with brine and dried (MgSO4) and the solvent was evaporated. The residue was chromatographed on silica gel (cyclohexane/ethyl acetate 9:1→1:1) to afford the title compound. Yield: 6.24 g (95% of theory); Mass spectrum (ESI+): m/z=316/318 (Br) [M+H]+.

1. temperatureThen, the solution was cooled to ambient temperature
2. stirringAfter stirring the solution at 65° C. for another 12 h
3. temperaturethe solution was cooled to ambient temperature
4. filtrationThe resulting mixture was filtered over Celite
5. customthe organic phase of the filtrate was separated
6. extractionThe aqueous phase of the filtrate was extracted with ethyl acetate
7. washThe combined organic phases were washed with brine
8. dry with materialdried (MgSO4)
9. customthe solvent was evaporated
10. customThe residue was chromatographed on silica gel (cyclohexane/ethyl acetate 9:1→1:1)

ORD record

ord-aea338f03d0f4c7e8aab2415cb54502f

Source dataset

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08754076B2