Acetic Acid → 1-(4-Bromothiophen-2-yl)-N,N-dimethylmethanamine

To a solution of 4-bromo-2-thiophene carboxaldehyde (5 g, 26.2 mmol) in 1,2-dichloroethane (50 mL) is added sodium triacetoxyborohydride (8.3 g, 39.3 mmol) and dimethylamine (14.5 mL, 28.8 mmol) followed by acetic acid (1.55 mL, 39.3 mmol). The mixture is stirred at room temperature for 2 hours. The insoluble is filtered and washed with diethyl ether. The mother liquor is concentrated. The resulting thick oil that is chromatographed through silica gel (dichloromethane-1.0M ammonia in methanol, 95:05 to 90:10 as eluant) to afford an orange oil. It is dissolved in dichloromethane and was washed with a saturated aqueous sodium bicarbonate solution. The organic layer is dried over magnesium sulfate and concentrated to produce (4-bromo-thiophen-2-ylmethyl)-dimethyl-amine [4.08 g, 71%, intermediate (1)] as an orange oil. LC/MS: RT=0.63 minutes, 219.99 m/e (M+H).

1. filtrationThe insoluble is filtered
2. washwashed with diethyl ether
3. concentrationThe mother liquor is concentrated
4. customThe resulting thick oil that is chromatographed through silica gel (dichloromethane-1.0M ammonia in methanol, 95:05 to 90:10 as eluant)
5. customto afford an orange oil
6. washwas washed with a saturated aqueous sodium bicarbonate solution
7. dry with materialThe organic layer is dried over magnesium sulfate
8. concentrationconcentrated

ORD record

ord-b08882be67724d4888e250d67c5a0a9a

Source dataset

uspto-grants-2011_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07928231B2