Methanol → 3-Bromo-2-hydroxybenzaldehyde

Over 0.25 hours 2-bromophenol (22.38 g, 129 mmol) was added to a solution of Mg(OMe)2 in methanol (111.9 ml, 8% w/w) and toluene (35 ml). The reaction was heated to reflux and maintained at reflux for 1 hour, then toluene (118 ml) was added. The solvent was distilled off until the temperature reached 92-94° C. A solution of paraformaldehyde in toluene was added portionwise over 1 hour at 80-90° C. and the reaction mixture heated to reflux and maintained at reflux for 3 hours. The reaction mixture was then allowed to cool to ambient temperature and left to stand overnight. Toluene (140 ml) was added to the reaction mixture, which was then washed with 2M H2SO4 (140 ml). The organic phase was dried and evaporated and the crude material used in the next step without further purification.

1. temperatureThe reaction was heated
2. temperatureto reflux
3. temperaturemaintained
4. temperatureat reflux for 1 hour
5. distillationThe solvent was distilled off until the temperature
6. customreached 92-94° C
7. additionA solution of paraformaldehyde in toluene was added portionwise over 1 hour at 80-90° C.
8. temperaturethe reaction mixture heated
9. temperatureto reflux
10. temperaturemaintained
11. temperatureat reflux for 3 hours
12. waitleft
13. additionToluene (140 ml) was added to the reaction mixture, which
14. washwas then washed with 2M H2SO4 (140 ml)
15. customThe organic phase was dried
16. customevaporated
17. customthe crude material used in the next step without further purification

ORD record

ord-acf6d4d5f2c14b4584da8c2fe5093901

Source dataset

uspto-grants-1999_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05965741