Hydrochloric Acid → HCID 67132157, compound

To a stirred solution of 2,6-dimethyl-4-fluorobenzyl bromide (4.89 g, 22.5 mmol) in DMF (100 ml) was added N-hydroxyphthalimide (3.67 g, 22.5 mmol) followed by drop-wise addition of triethylamine (3.5 ml, 25.1 mmol). The reaction mixture was stirred at room temperature for 2 hours. The mixture was poured into 1M HClaq. and the resulting white precipitate was isolated by filtration, washed with water and dried in vacuo. This phthalimide intermediate (6.51 g, 21.9 mmol) was treated with hydrazine monohydrate (1.06 ml, 21.8 mmol) in ethanol (60 ml) at reflux for 3 hours. The mixture was cooled to room temperature and ether was added. The precipitated material was removed by filtration, and the filtrate was evaporated under reduced pressure. The residue was suspended in EtOAc and filtrated. 4M HCl in dioxane (22 mmol) was added to the filtrate and the resulting precipitate was isolated by filtration and dried under vacuum, and gave the title compound (3.92 g) as a white powder. 13C-NMR (DMSO-d6) δ 161.9, 141.8, 126.5, 114.3, 69.3, 19.2. Alternatively, the phthalimide intermediate can be treated with hydrazine monohydrate (1 eq.) in dichloromethane at room temperature for 20 to 24 hours, remove the formed solids by filtration and evaporate the filtrate to obtain the free hydroxylamine.

1. additionThe mixture was poured into 1M HClaq
2. customand the resulting white precipitate was isolated by filtration
3. washwashed with water
4. customdried in vacuo
5. temperatureat reflux for 3 hours
6. temperatureThe mixture was cooled to room temperature
7. customThe precipitated material was removed by filtration
8. customthe filtrate was evaporated under reduced pressure
9. filtrationfiltrated
10. customthe resulting precipitate was isolated by filtration
11. customdried under vacuum

ORD record

ord-ee8b9ed921fc4e74af059340977bcb95

Source dataset

uspto-grants-2011_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08034811B2