Hydrochloric Acid → HCID 13703687, compound

In a 500 ml Erlenmyer flask 5-bromovanillin (6.3 g, 26.8 mmol) was dissolved in 4% NaOH (40 mL) and degasseal with N2 for 20 min. Hydrogen peroxide (Baker, 30%, 5 mL diluted with 40 mL of water) was added to the stirring 5-bromovanillin solution. Heating was observed but the reaction did not reflux. The reaction was allowed to stir under N2 for 1 h. HCl (concd, 10 mL) was added in portions to prevent over foaming. Ferric chloride, hydrated (Baker, 8 g) dissolved in water (20 mL), was added all at once and the reaction was allowed to stir for 1 h. The resulting precipitate was collected and washed with water (20 mL). The dark solid was filtered through a pad of silica gel (5×3 cm) using CHCl3 as solvent. The resulting yellow solid was crystalized from methanol giving orange needles, (4.2 g, 72%, one spot on TLC and > 95% pure by 1H NMR), mp 157°-158° C. (lit, 161°-162° C.), 1H NMR (CDCl3) δ3.86 (s, 3H), 5.96 (d, J=2 Hz, 1H), 7.21 (d, J=2 Hz, 1H).

1. temperatureHeating
2. temperaturethe reaction did not reflux
3. additionwas added all at once and the reaction
4. stirringto stir for 1 h
5. customThe resulting precipitate was collected
6. washwashed with water (20 mL)
7. filtrationThe dark solid was filtered through a pad of silica gel (5×3 cm)
8. customThe resulting yellow solid was crystalized from methanol giving orange needles, (4.2 g, 72%, one spot on TLC and > 95% pure by 1H NMR), mp 157°-158° C. (lit, 161°-162° C.), 1H NMR (CDCl3) δ3.86 (s, 3H), 5.96 (d, J=2 Hz, 1H), 7.21 (d, J=2 Hz, 1H)

ORD record

ord-ea8b9f41d4ff44c3b70e50593e5cd3f4

Source dataset

uspto-grants-1995_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05476933