Diisopropylethylamine → (+)-2-bromo-N-(7-[1,4]dioxan-2-yl-4-methoxy-benzothiazol-2-yl)-isonicotinamide

Participants

Reaction Steps

To a stirred solution of 789 mg (3.91 mmol) 2-bromo-isonicotinic acid in 50 ml THF were added 1.71 g (4.51 mmol) HATU and 1.29 ml (7.51 mmol) N-ethyldiisopropylamine and stirring continued at room temperature for 2 h. 800 mg (3.00 mmol) (+)-7-[1,4]dioxan-2-yl-4-methoxy-benzothiazol-2-ylamine was then added and stirring continued at room temperature for 24 h. The reaction mixture was then poured into saturated aqueous sodium bicarbonate solution and extracted three times with ethyl acetate. The combined organic phases were dried over sodium sulfate and concentrated in vacuo. Flash chromatography (acetone) followed by trituration in ether afforded 1.35 g (99%) (+)-2-bromo-N-(7-[1,4]dioxan-2-yl-4-methoxy-benzothiazol-2-yl)-isonicotinamide as a light yelllow solid. [α]D20=+12.9° (c=0.76, CHCl3), ES-MS m/e (%):452 (M{81Br}+H+, 95), 450 (M{79Br}+H+, 100).

Provenance & Evidence