Potassium Acetate → (2-(Tert-butoxycarbonyl)-1,2,3,4-tetrahydroisoquinolin-6-YL)boronic acid pinacol ester

Participants

Reaction Conditions

Reaction Steps

A solution of tert-butyl 6-bromo-3,4-dihydroisoquinoline-2(1H)-carboxylate and tert-butyl 8-bromo-3,4-dihydroisoquinoline-2(1H)-carboxylate (19.5 mmol), bis(pinacolato)diboron (21.4 mmol) and potassium acetate (61 mmol) in DMF (100 mL) was degassed. To this solution was added PdCl2dppf (1:1 complex with DCM, 0.8 mmol). The reaction mixture was heated at 85° C. for 4 hr and then allowed to cool to room temperature and diluted with EtOAc. The solution was washed with water and brine, dried over Na2SO4, filtered and concentrated. The residue was purified by column chromatography to give tert-butyl 6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,4-dihydroisoquinoline-2(1H)-carboxylate and tert-butyl 8-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,4-dihydroisoquinoline-2(1H)-carboxylate. LCMS: (FA) ES+ 360 (for each).

Provenance & Evidence