Hydrochloric Acid → 3-formylbenzamide

Temperature

23 °C

Oxalyl chloride (13.3 mL, 152 mmol) and DMF (50 μL) were added to suspension of 3-carboxybenzaldehyde (11.4 g, 76.2 mmol) in 200 mL CH2Cl2 and stirred at 23° C. for 18 h. The resulting clear solution was concentrated, dissolved in 100 mL CH2Cl2, and concentrated again. The crude acid chloride was dissolved in 20 mL THF, poured into a mixture of concentrated NH4OH (26 mL, 381 mmol) with 100 mL crushed ice, and allowed to warm to 23° C. with stirring. The mixture was acidified with conc. HCl to pH ˜3, then concentrated to remove THF. The resulting aqueous suspension was filtered and the white solid product dried under vacuum to give 7.4 g (65%) of 3-carbamoyl-benzaldehyde compound 1a: 1H NMR (DMSO-d6)δ 10.06 (1 H, s), 8.40 (1 H, s), 8.19 (1 H, s), 8.17 (1 H, d, J=6.6 Hz), 8.04 (1 H, d, J=7.7 Hz), 7.69 (1 H, t, J=7.7 Hz), 7.56 (1 H, s); IR (KBr pellet) 3391, 3205, 1711, 1694, 1664, 1385, 1217. Anal. (C8H7NO2•0.1H2O) C, H, N.

1. concentrationThe resulting clear solution was concentrated
2. dissolutiondissolved in 100 mL CH2Cl2
3. concentrationconcentrated again
4. dissolutionThe crude acid chloride was dissolved in 20 mL THF
5. customcrushed ice
6. temperatureto warm to 23° C.
7. stirringwith stirring
8. concentrationconcentrated
9. customto remove THF
10. filtrationThe resulting aqueous suspension was filtered
11. customthe white solid product dried under vacuum

ORD record

ord-5446c184cbf049419f1329529c7ed678

Source dataset

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06369226B1