Boron trifluoride → (2-Fluoro-5-methoxy-4-nitrophenyl)methanol

HRID 1947894Notes

Reaction equation

[F:1][C:2]1[CH:10]=[C:9]([N+:11]([O-:13])=[O:12])[C:8]([O:14][CH3:15])=[CH:7][C:3]=1[C:4](O)=[O:5].[BH4-].[Na+].B(F)(F)F>C1COCC1>[F:1][C:2]1[CH:10]=[C:9]([N+:11]([O-:13])=[O:12])[C:8]([O:14][CH3:15])=[CH:7][C:3]=1[CH2:4][OH:5]

Participants

Conditions

Temperature: 0 °C

Procedure

A solution of 2-fluoro-5-methoxy-4-nitrobenzoic acid (Compound 130E, 1.60 g, 7.44 mmol) in THF (23.6 mL) is slowly charged with sodium borohydride (0.633 g, 16.8 mmol) and stirred for 5 minutes. A solution of boron trifluoride, ethyl ether complex (0.895 mL, 7.26 mmol) in THF (7.85 mL) is added to the reaction mixture. The resulting solution is heated at reflux for 4 h. The reaction mixture was cooled to 0° C., then quenched with ice (15 mL) and diluted with ether (25 mL) and 2 N NaOH (10 mL). The ether layer was washed with brine (15 mL), dried over Na2SO4, filtered and concentrated under reduced pressure to yield an off-white solid, 1.45 g (97% yield). This material was used without any further purification. 1H NMR (CDCl3, 400 MHz): δ=3.99 (s, 3H), 4.86 (s, 2H), 7.29 (d, J=5.81 Hz, 1H), 7.64 (d, J=9.09 Hz, 1H). MS (ES+): m/z 202.05 [MH+] (TOF, polar).

Workup

temperatureThe resulting solution is heated
temperatureat reflux for 4 h
customquenched with ice (15 mL)
additiondiluted with ether (25 mL) and 2 N NaOH (10 mL)
washThe ether layer was washed with brine (15 mL)
dry with materialdried over Na2SO4
filtrationfiltered
concentrationconcentrated under reduced pressure
customto yield an off-white solid, 1.45 g (97% yield)
customThis material was used without any further purification

Sources & evidence

ORD record: ord-b2609c17f05a45abaafa2008f74a25dc
Source dataset: uspto-grants-2013_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08399433B2

Reaction notes

Loading…