2-Fluoro-6-methoxynaphthalene → 6-Fluoronaphthalen-2-ol

Temperature

0 °C

A flask was charged with 2-fluoro-6-methoxynapthalene (3.80 g, 21.6 mmol) and dichloromethane (86 mL) and cooled to 0° C. in an icebath under a flow of nitrogen. A solution of borontribromide (26 mL of a 1M solution in dichloromethane, 25.9 mmol) was added via cannula. The reaction solution was stirred 15 minutes at 0° C., the cooling bath was removed and the reaction was stirred for 1.5 h at ambient temperature. The reaction was quenched by slowly adding excess 10% aqueous hydrochloric acid. The two-phased reaction mixture was partitioned between ethyl acetate and water. The organic layer was washed (2x, brine), dried (Na2SO4), filtered and concentrated in vacuo to afford a brown gummy solid. Purification by flash chromatography (silica gel; 20% ethyl acetate/hexane) afforded the desired product (3.63 g, 91% yield). Recrystallization from cold ether/hexanes provided the title compound as a colorless powdery solid. mp 118°-120° C.; 1HNMR (300 MHz, DMSO-d6) δ 7.11-7.18 (m; 2H), 7.30 (td; J=9,9,3 Hz; 1H), 7.55 (dd; J=10.5,3 Hz; 1H), 7.73-7.79 (m; 2H), 9.73 (s; 1H).

1. customthe cooling bath was removed
2. stirringthe reaction was stirred for 1.5 h at ambient temperature
3. customThe reaction was quenched by slowly adding excess 10% aqueous hydrochloric acid
4. customThe two-phased reaction mixture
5. customwas partitioned between ethyl acetate and water
6. washThe organic layer was washed (2x, brine)
7. dry with materialdried (Na2SO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customto afford a brown gummy solid
11. customPurification by flash chromatography (silica gel; 20% ethyl acetate/hexane)

ORD record

ord-fe15546da8004887bcdf6da6bff792bc

Source dataset

uspto-grants-1997_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05681842