2-Chlorophenothiazine → 1-sec-butyl-10H-phenothiazine

Temperature

-78 °C

The stirred solution of 2-chlorophenothiazine (5.02 g, 21.54 mmol) in anhydrous THF (50 mL) was cooled to −78° C. and under argon sec-butyl lithium (77 mL, 108 mmol) was added drop-wise. After all the addition, the resulting orange mixture was stirred at −78° C. for 3 h, then was allowed to warm to room temperature. The reaction was quenched by the slow addition of saturated ammonium chloride, extracted with ethyl acetate (2×400 mL). The combined organics were washed with brine, dried (MgSO4), filtered, concentrated, and purified by chromatography, using ethyl acetate-hexane gradient to afford 1-sec-butyl-10H-phenothiazine. MS (m/z): [M+H]+=256. To the solution of 1-sec-butyl-10H-phenothiazine (1.0 g, 4.14 mmols) in chloroform (30 mL), at 5° C. was added the solution of iodine (3.2 g, 12.61 mmol) in chloroform (125 mL) drop-wise. After the addition the resulting dark mixture was stirred at 5° C. overnight. Product was filtered, washed several times with chloroform, dried to afford the title compound (1.8 g, 68%).

1. additionwas added drop-wise
2. additionAfter all the addition
3. temperatureto warm to room temperature
4. customThe reaction was quenched by the slow addition of saturated ammonium chloride
5. extractionextracted with ethyl acetate (2×400 mL)
6. washThe combined organics were washed with brine
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated
10. custompurified by chromatography

ORD record

ord-f2d9e02a74a9457091fb9f037a71f9ac

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08828986B2