Hydrochloric Acid → HCID 66759651, compound

Temperature

0 °C

To a suspension of 7-bromo-benzothiazol-6-ylamine (7.6 g, 33.3 mmol) in water (60 mL) was added concentrated hydrochloric acid (6 mL, 72 mmol). The mixture was cooled to 0° C. and stirred for 10 min. A cooled (0° C.) solution of sodium nitrite (5.0 g, 73 mmol) in water (10 mL) was added dropwise to the reaction mixture keeping the internal temperature below 5° C. The mixture was stirred for further 10 min. A solution of potassium iodide (12.1 g, 73 mmol) in water (15 mL) was added to the reaction mixture and was stirred vigorously for 10 min, and then water (200 mL) and 20% aqueous sodium thiosulfate solution (100 mL) were added. The solid formed was extracted with ethyl acetate (3×70 mL). The combined organic fractions were washed with water (100 mL), dried over anhydrous sodium sulfate, and concentrated. Purification of the residue by column chromatography (25% ethyl acetate:hexanes) afforded 0.3 g (5%) of the title compound, plus some impure title compound. The impure title compound was recrystallized 2× from 1:4 DCM:hexanes to afford a further 0.71 g (9%) of the title compound. 1H NMR (300 MHz, CDCl3): δ 8.99 (s, 1H), 7.95 (d, J=8.4, 1H), 7.77 (d, J=8.4 Hz, 1H).

1. additionwas added dropwise to the reaction mixture
2. customthe internal temperature below 5° C
3. stirringThe mixture was stirred for further 10 min
4. stirringwas stirred vigorously for 10 min
5. customThe solid formed
6. extractionwas extracted with ethyl acetate (3×70 mL)
7. washThe combined organic fractions were washed with water (100 mL)
8. dry with materialdried over anhydrous sodium sulfate
9. concentrationconcentrated
10. customPurification of the residue by column chromatography (25% ethyl acetate:hexanes)

ORD record

ord-c0b285f54991407c8be56ed931932c99

Source dataset

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08378104B2