Hydrochloric Acid → 2-Propoxymethylphenylboric acid

Temperature

60 °C

To a mixture of magnesium (0.83 g) and THF (30 ml) was added 1,2-dibromoethane (0.1 ml) at room temperature and subsequently was added dropwise a solution of 2-bromobenzyl propyl ether (7.88 g) in THF (40 ml) at 60° C. over a period of 30 minutes, under an argon atmosphere. After the dropwise addition, the resulting mixture was stirred further at 60° C. for 2 hours and was then cooled to −78° C., and a solution of trimethylboric acid (12 ml) in THF (24 ml) was added dropwise. The resulting mixture was stirred at 78° C. for one hour and then at room temperature for 10 hours. To the reaction mixture was added 1 N hydrochloric acid (100 ml), and the resulting mixture was stirred for 30 minutes and was then extracted with ethyl acetate. The organic layer was washed with an aqueous saturated solution of sodium chloride and was dried with magnesium sulfate. After concentration under reduced pressure, the precipitated crystals were collected by filtration. The crystals were washed with hexane to obtain 2-propoxymethylphenylboric acid (2.95 g) as colorless crystals.

1. additionAfter the dropwise addition
2. temperaturewas then cooled to −78° C.
3. stirringThe resulting mixture was stirred at 78° C. for one hour
4. waitat room temperature for 10 hours
5. stirringthe resulting mixture was stirred for 30 minutes
6. extractionwas then extracted with ethyl acetate
7. washThe organic layer was washed with an aqueous saturated solution of sodium chloride
8. dry with materialwas dried with magnesium sulfate
9. concentrationAfter concentration under reduced pressure
10. filtrationthe precipitated crystals were collected by filtration
11. washThe crystals were washed with hexane

ORD record

ord-da8d7ee9e84f4cacb1374e99694fb4bf

Source dataset

uspto-grants-2003_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06627651B1