Hydrochloric Acid → HCID 178419566, compound

Raney nickel (10.95 g) was washed with water (4×300 ml) then with methanol (4×300 ml). The catalyst was suspended in 450 ml of methanol and 4-(2-bromoethoxy)-6-nitroaniline (5.08 g, 19.46 mmol) was added. The reaction mixture was stirred under a hydrogen atmosphere (1 atm) at room temperature for 1.5 h. After removal of the catalyst by filtration, the filtrate was evaporated to give a black residue. The black residue was redissolved in a mixture of ethyl acetate (200 ml) and methanol (50 ml). Etheral HCl solution (1N, 40 ml) was added slowly to precipitate the diamine as the hydrochloride salt. The purple solid was collected and dissolved in a mixture of acetic acid (25 ml) and water (50 ml). The reaction mixture was cooled to 5° C. in an ice-bath. A solution of sodium nitrite (1.75 g, 25.36 mmol) in 10 ml water was added slowly into the reaction mixture. The mixture was heated at 80° C. for 3 h. The solid was collected by filtration and washed with water (3×30 ml). The solid was dissolved in THF and dried over magnesium sulphate, filtered and concentrated. The residue was chromatographed on silica gel eluted with 50% ethyl acetate in hexanes to give 2.15 g of 6-(2-bromoethoxy)-1H-benzotriazole as a white solid. 1H NMR (CDCl3) 7.86 (1h, d, J=9.03), 7.11-7.05 (2H, m), 4.34 (2H, t, J=6.10), 3.67 (2H, t, J=6.10).

1. washRaney nickel (10.95 g) was washed with water (4×300 ml)
2. customAfter removal of the catalyst
3. filtrationby filtration
4. customthe filtrate was evaporated
5. customto give a black residue
6. customto precipitate the diamine as the hydrochloride salt
7. customThe purple solid was collected
8. dissolutiondissolved in a mixture of acetic acid (25 ml) and water (50 ml)
9. temperatureThe reaction mixture was cooled to 5° C. in an ice-bath
10. temperatureThe mixture was heated at 80° C. for 3 h
11. filtrationThe solid was collected by filtration
12. washwashed with water (3×30 ml)
13. dissolutionThe solid was dissolved in THF
14. dry with materialdried over magnesium sulphate
15. filtrationfiltered
16. concentrationconcentrated
17. customThe residue was chromatographed on silica gel
18. washeluted with 50% ethyl acetate in hexanes

ORD record

ord-1efd1b9e56414c4f9c6e79e929f0ec33

Source dataset

uspto-grants-2000_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06124323