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

Participants

Reaction Conditions

Reaction Steps

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%).

Provenance & Evidence