Acetyl chloride → Benzoic acid, 3-(acetyloxy)-4-methoxy-

To a suspension of 600 mg (3.57 mmol) of 3-hydroxy-4-methoxybenzoic acid (Aldrich Chemical Company, Milwaukee, Wis.) in 5 mL of anhyd CH2Cl2 was added 1.31 mL (7.50 mmol) of N,N-diisopropylethylamine and the mixture stirred until homogeneous (ca. 5 min). Acetyl chloride (305 μL, 4.28 mmol) was added dropwise over 2 min followed by 2.0 mg ((0.016 mmol) of 4-dimethylaminopyridine. After stirring at room temperature for 1 h, the mixture was poured into 50 mL of EtOAc and washed with 1 M HCl (3×25 mL). The organic phase was extracted with saturated NaHCO3 (6×15 mL) and the combined extracts saturated with solid NaCl and acidified to pH 2 with conc HCl. The resulting suspension was extracted with EtOAc (3×20 mL) and the combined extracts were dried over Na2SO4 and concentrated in vacuo to afford the title compound as a light beige powder (463 mg, 62%). 1H-NMR (300 MHz, CDCl3) δ8.00 (dd, 1H, J=8.7, 2.0 Hz), 7.79 (d, 1H, 2.0 Hz), 7.00 (d, 1H, 8.7 Hz), 3.91 (s, 3H), and 2.34 (s, 3H).

1. stirringAfter stirring at room temperature for 1 h
2. washwashed with 1 M HCl (3×25 mL)
3. extractionThe organic phase was extracted with saturated NaHCO3 (6×15 mL)
4. extractionThe resulting suspension was extracted with EtOAc (3×20 mL)
5. dry with materialthe combined extracts were dried over Na2SO4
6. concentrationconcentrated in vacuo

ORD record

ord-4d6363ba455e4f4a8f57a63b8f1f2a74

Source dataset

uspto-grants-2002_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06492403B1