Triisopropyl borate → Isoquinoline-4-boronic acid

A solution of 4-bromoisoquinoline in tetrahydrofuran is cooled to -78° C. To this solution is added dropwise n-butyllithium (1.6 M in hexane), and the resultant solu-tion is stirred for 30 minutes. To this solution is then added dropwise triisopropylborate and the reaction mixture is then stirred for 18 hours at room temperature. The reaction mixture is then partitioned between ethyl acetate and saturated aqueous sodium chloride. The phases are separated and the aqueous phase extracted well with ethyl acetate. The combined organic phases are washed with saturated aqueous sodium chloride, dried over sodium sulfate and concentrated under reduced pressure. The residue is sonicated in a mixture of hexane:ethyl acetate. The resulting suspension is filtered to provide isoquinolin-4-ylboronic acid.

1. stirringthe reaction mixture is then stirred for 18 hours at room temperature
2. customThe reaction mixture is then partitioned between ethyl acetate and saturated aqueous sodium chloride
3. customThe phases are separated
4. extractionthe aqueous phase extracted well with ethyl acetate
5. washThe combined organic phases are washed with saturated aqueous sodium chloride
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe residue is sonicated in a mixture of hexane
9. filtrationThe resulting suspension is filtered

ORD record

ord-63d0251e1ae148ebb468b99c91895dcf

Source dataset

uspto-grants-2000_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06107307