Sodium borohydride → tert-Butyl 8-bromo-4-hydroxy-3,4-dihydroisoquinoline-2(1H)-carboxylate

Participants

Reaction Steps

To a flask containing tert-butyl 8-bromo-4-oxo-3,4-dihydroisoquinoline-2(1H)-carboxylate (24-3) (644 mg, 1.974 mmol) was added anhydrous THF (5 ml), followed by NaBH4 (399 mg, 10.55 mmol). The reaction mixture was then capped (not under N2) & stirred at room temperature. Followed by LC/MS. After 10 minutes the reaction mixture was quenched with saturated NaHCO3, then suspended in EtOAc, washed with saturated NaHCO3, then H2O, then brine; organics dried over Na2SO4, filtered & concentrated. Purification by silica gel chromatography (0-50% EtOAc/Hex; 40 g ISCO); desired fractions concentrated to yield tert-butyl 8-bromo-4-hydroxy-3,4-dihydroisoquinoline-2(1H)-carboxylate (24-4). HRMS [M+H]: calculated; 328.0543, observed; 328.0537.

Provenance & Evidence