Dimethylformamide → 4-[2-(1-Pyrrolidinyl)ethoxy]benzamide

To a suspension of 4-[2-(1-pyrrolidinyl)ethoxy]benzoic acid hydrochloride (750 mg, 2.76 mmol) in dry dichloromethane (10 mL) was added oxalyl chloride (0.481 mL, 5.62 mmol, 2.0 eq.) then a catalytic amount of DMF. After 1 h, the reaction mixture was filtered through a pad of diatomaceous earth, then the solvent was removed under reduced pressure. The residue was treated with excess concentrated ammonium hydroxide in THF (5 mL each). The layers were separated by the addition of brine (10 mL); then the aqueous layer was extracted with THF (2×20 mL). The combined extracts were concentrated to dryness under reduced pressure to give the desired amide as a white solid (602 mg, 93%) after drying under vacuum at ambient temperature.

1. filtrationthe reaction mixture was filtered through a pad of diatomaceous earth
2. customthe solvent was removed under reduced pressure
3. additionThe residue was treated with excess concentrated ammonium hydroxide in THF (5 mL each)
4. customThe layers were separated by the addition of brine (10 mL)
5. extractionthen the aqueous layer was extracted with THF (2×20 mL)
6. concentrationThe combined extracts were concentrated to dryness under reduced pressure

ORD record

ord-803d74c888fe4416b73955a90e12c1b9

Source dataset

uspto-grants-2003_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06541499B1