Diethanolamine → 4-(4-(3-Cyano-4-(ethylsulfonyl)phenylamino)-4-oxobutyl)phenylboronic acid

Participants

Reaction Conditions

Reaction Steps

A flask containing 6C (83 mg, 0.19 mmol), 5,5,5′,5′-tetramethyl-[2,2′]bi[[1,3,2]dioxaborinanyl] (47.6 mg, 0.211 mmol), potassium acetate (83 mg, 0.84 mmol), and dichloro[1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (4.4 mg, 0.0060 mmol) was purged with argon. DMSO (1 mL) was added, and the reaction mixture was degassed with three cycles of vacuum followed by argon backfill. The reaction mixture was heated for 2 h at 80° C., cooled to rt, and diluted with water (100 mL). The aqueous solution was extracted with diethyl ether (3×25 mL), dried (MgSO4), and concentrated under reduced pressure. The residue was dissolved in a mixture of diethyl ether (1 mL), DCM (˜0.1 mL), and EtOAc (˜0.1 mL). Diethanolamine (22 mg, 0.21 mmol) in isopropanol (0.5 mL) was added, and the reaction mixture was stirred overnight at rt. The reaction mixture was concentrated, and the residue was purified by reverse phase HPLC (under the standard acidic conditions) to give 6D (44 mg, 57%) as a clear oil. MS (ESI) m/z 425.4 (M+CH3OH—H2O+H)+.

Provenance & Evidence