Dimethylformamide → 4-Formyl-2-methylbenzoic acid
Reaction equation
Br[C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[C:4]([CH3:11])[CH:3]=1.C([Li])CCC.CN(C)[CH:19]=[O:20]>C1COCC1>[CH:19]([C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[C:4]([CH3:11])[CH:3]=1)=[O:20]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- -78 °C
Procedure
To 4-bromo-2-methyl benzoic acid (2.50 g, 11.6 mmol) suspended in anhydrous THF (90 ml) at −78° C. was added n-butyl lithium (9.8 ml, 2.5 M in hexane) and dimethylformamide (2.0 ml). The reaction was stirred at −78° C. for 1 h and then warmed to 25° C. and allowed to react for an additional hour. The reaction was quenched with 1 N aqueous hydrochloric acid and extracted with ethyl acetate. The organic layer was extracted with 1 N aqueous sodium hydroxide and the aqueous layer was separated and the pH adjusted with 1 N aqueous hydrochloric acid. The aqueous phase was extracted with ethyl acetate, then washed with brine, dried over sodium sulfate, filtered and concentrated. The resulting crude 4-formyl-2-methylbenzoic acid (900 mg, 47%) was obtained and was used without further purification. 1H NMR (400 MHz, CD3OD): 10.02-10.00 (s, 1H), 8.04-8.01 (d, 1H), 7.81-7.76 (m, 2H), 2.66-2.63 (s, 3H). MS (EI) for C9H8O3: 163 (M−).
Workup
- temperaturewarmed to 25° C.
- customto react for an additional hour
- customThe reaction was quenched with 1 N aqueous hydrochloric acid
- extractionextracted with ethyl acetate
- extractionThe organic layer was extracted with 1 N aqueous sodium hydroxide
- customthe aqueous layer was separated
- extractionThe aqueous phase was extracted with ethyl acetate
- washwashed with brine
- dry with materialdried over sodium sulfate
- filtrationfiltered
- concentrationconcentrated
Sources & evidence
- ORD record
- ord-216c9b7722d04d979a6305e0cd3bee92
- Source dataset
- uspto-grants-2011_09
- Patent number
- US08012956B2
Reaction notes
Loading…