Ammonium Chloride → 1,2-Benzisothiazol-5-amine, 3-chloro-

Temperature

80 °C

A solution of 3-chloro-5-nitrobenzo[d]isothiazole (4.53 g, 21.1 mmol), iron (7.2 g, 129 mmol) and ammonium chloride (2.4 g, 45 mmol) in ethanol/water (2:1, 270 mL) is allowed to stir at 80° C. for 1.5 h. The resulting dark reaction mixture was filtered through Celite while still hot and concentrated under reduced pressure to give a brown solid, which was dissolved in ethyl acetate and washed with saturated aqueous sodium bicarbonate solution and brine. The resulting organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to give a brown solid which was triturated with hexanes to provide 3-chlorobenzo[d]isothiazol-5-amine (3.7 g) as a yellow solid. 1H NMR (300 MHz, CDCl3): 7.57 (dd, 1H), 6.99 (dd, 1H), 6.66 ppm (dd, 1H). MW=184 confirmed by LC-MS, tr=10.41 min (Method Y) MH+=185.

1. customThe resulting dark reaction mixture
2. filtrationwas filtered through Celite while still hot and
3. concentrationconcentrated under reduced pressure
4. customto give a brown solid, which
5. washwashed with saturated aqueous sodium bicarbonate solution and brine
6. dry with materialThe resulting organic layer was dried over anhydrous magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customto give a brown solid which
10. customwas triturated with hexanes

ORD record

ord-045085b7cbc54471a98fc0b17943f262

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07776847B2