Dimethylformamide → 3-Bromo-5-methoxybenzaldehyde

Temperature

-78 °C

A solution of 1,3-dibromo-5-methoxybenzene (5.00 g, 18.8 mmol) in anhydrous diethyl ether (100 mL) was cooled to −78° C. Then a solution of n-butyllithium in hexanes (2.5 M, 8.3 mL, 20.68 mmol) was added drop-wise at −78° C. under nitrogen. After the addition was complete, the reaction was stirred at −78° C. for 45 min. After that time, anhydrous DMF (7.3 mL), 94.0 mmol) was added, the cooling bath was removed and the reaction mixture was allowed to warm to rt. The reaction was diluted with saturated aqueous NH4Cl solution (100 mL) and diethyl ether (100 mL). The organic phase was separated, washed with water, dried over anhydrous Na2SO4 and concentrated under reduced pressure to give 3-bromo-5-methoxybenzaldehyde (3.95 g, 98%) as yellow oil: 1H NMR (400 MHz, CDCl3) δ 9.90 (s, 1H), 7.57-7.60 (m, 1H), 7.31-7.33 (m, 2H), 3.86 (s, 3H).

1. additionAfter the addition
2. customthe cooling bath was removed
3. temperatureto warm to rt
4. additionThe reaction was diluted with saturated aqueous NH4Cl solution (100 mL) and diethyl ether (100 mL)
5. customThe organic phase was separated
6. washwashed with water
7. dry with materialdried over anhydrous Na2SO4
8. concentrationconcentrated under reduced pressure

ORD record

ord-569f30b811a44d898458e0bf43edfc88

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09278940B2