Phosphorus oxychloride → 7-Bromo-2-chloro-1,6-naphthyridine

Temperature

80 °C

7-Bromo-1,6-naphthyridin-2(1H)-one (Preparation 67, 800 mg 3.55 mmole) was treated with phosphorus oxychloride (18 mL) and catalytic DMF (2 drops). The reaction was heated at 80° C. for 2.5 hours. The phosphorus oxychloride was evaporated and the residue was azeotroped with toluene (15 mL). The solid was partitioned between ethyl acetate (50 mL) and saturated aqueous sodium bicarbonate solution (30 mL) with ice (10 g). The aqueous layer was washed with EtOAc, the organic layers combined, washed with sodium bicarbonate solution, brine, dried over sodium sulphate and concentrated in vacuo to afford the title compound (826 mg, 95%).

1. customThe phosphorus oxychloride was evaporated
2. customthe residue was azeotroped with toluene (15 mL)
3. customThe solid was partitioned between ethyl acetate (50 mL) and saturated aqueous sodium bicarbonate solution (30 mL) with ice (10 g)
4. washThe aqueous layer was washed with EtOAc
5. washwashed with sodium bicarbonate solution, brine
6. dry with materialdried over sodium sulphate
7. concentrationconcentrated in vacuo

ORD record

ord-e88d3e9699f8475494a908bf0f4b31cc

Source dataset

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09334286B2