反应详情

温度

60 °C

To a solution of 5-amino-2-methylbenzothiazole (818 mg, 4.99 mmol) in isopropanol (12 mL) was added N-chlorosuccinimide (732 mg, 5.48 mmol). The mixture was stirred at 60° C. for 15 min., partitioned between DCM and 5% sodium bicarbonate. The organic phase was washed with brine, dried over sodium sulphate and concentrated in vacuo to give a residue that was purified with flash chromatography (EtOAc/DCM gradient elution). 4-Chloro-2-methylbenzothiazol-5-ylamine was obtained as off-white crystalline solid (510 mg, 51%). mp 121-122° C. (lit. 124° C.); TLC single spot at Rf 0.51 (20% EtOAc/DCM); 1H NMR (270 MHz, DMSO): δ 7.61 (1H, d, J=8.6 Hz, ArH), 6.91 (1H, d, J=8.6 Hz, ArH), 5.49 (2H, s, NH2), 2.75 (3H, s, CH3); APCI-MS 199 (MH)+.

1. custompartitioned between DCM and 5% sodium bicarbonate
2. washThe organic phase was washed with brine
3. dry with materialdried over sodium sulphate
4. concentrationconcentrated in vacuo
5. customto give a residue that
6. customwas purified with flash chromatography (EtOAc/DCM gradient elution)