Hydrochloric Acid → 9-Anthraceneboronic Acid

Temperature

-40 °C

9-Bromoanthracene 38.6 g was dissolved in dehydrated toluene 80 ml and dehydrated THF (tetrahydrofuran) 160 ml, and the solution was cooled to −40° C. A 1.58M n-butyllithium hexane solution 106 ml was dropwise added thereto and stirred at −40° C. for 30 minutes, the temperature was elevated up to −10° C. The solution was cooled again down to −70° C., and a dehydrated THF solution of trimethyl borate 50.0 ml was gradually dropwise added thereto. The solution was stirred at −70° C. for 2 hours and then slowly heated up to room temperature. After left standing for a night, a 10% hydrochloric acid aqueous solution 100 ml was added thereto and stirred, and then it was extracted twice with toluene. The organic layer was washed with saturated brine and dried on anhydrous sodium sulfate. The solvent was distilled off, and the residue was crystallized from toluene/hexane, filtered and dried, whereby targeted 9-anthraceneboronic acid 24.4 g was obtained in the form of pale brown crystal (yield: 73%).

1. customwas elevated up to −10° C
2. temperatureThe solution was cooled again down to −70° C.
3. stirringThe solution was stirred at −70° C. for 2 hours
4. temperatureslowly heated up to room temperature
5. waitAfter left standing for a night
6. stirringstirred
7. extractionit was extracted twice with toluene
8. washThe organic layer was washed with saturated brine
9. dry with materialdried on anhydrous sodium sulfate
10. distillationThe solvent was distilled off
11. customthe residue was crystallized from toluene/hexane
12. filtrationfiltered
13. customdried

ORD record

ord-25684892488041d6bc926e998e4c2101

Source dataset

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08568902B2