Ethyldiphenylphosphine → tert-butyl 3-(3-acetamido-3-(tert-butylcarbamoyl)-7-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)heptyl)-3,4-dihydroisoquinoline-2(1H)-carboxylate

Participants

Reaction Steps

While under an atmosphere of argon, a solution of bis(1,5-dicyclooctadiene)diiridium(I) dichloride (54 mg, 3% mol), diphenylphosphinoethane (64 mg, 6% mol) and 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.5 mL, 10.7 mmol) in dry dichloromethane (20 mL) was cooled to 0° C. A second solution of tert-butyl 3-(3-acetamido-3-(tert-butylcarbamoyl)oct-7-enyl)-3,4-dihydroisoquinoline-2(1H)-carboxylate (1.5 g, 2.67 mmol) in dry dichloromethane (20 mL) was added in one portion. After 4 h LCMS indicated all the starting olefin was consumed and the reaction was washed successively with water, sat'd aq sodium chloride, dried over MgSO4, filtered and concentrated. Purification by flash chromatography (20-35% ethyl acetate in hexanes) gave tert-butyl 3-(3-acetamido-3-(tert-butylcarbamoyl)-7-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)heptyl)-3,4-dihydroisoquinoline-2(1H)-carboxylate as a yellow oil (1.5 g, 93%). ESI MS found for C34H56BN3O6 m/z [614.7 (M+1), 633.7 (M+23)].

Provenance & Evidence