Tetrahydrofuran → 2-acetamido-N-tert-butyl-2-((R)-1-(4-fluorobenzyl)pyrrolidin-3-yl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)hexanamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of bis(1,5-cyclooctadiene)diiridium(I) dichloride (35.0 mg, 0.0520 mmol) and 1,2-bis(diphenylphosphino)-ethane (44 mg, 0.11 mmol) in tetrahydrofuran (5 mL, 60 mmol) was cooled to 0° C. After stirring for 10 min 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (120 uL, 0.83 mmol) was added in a single portion via syringe and the reaction mixture was stirred at 0° C. for 5 min before warming to room temperature and stirring an additional 15 min. The reaction mixture was recooled to 0° C. and treated with 2-acetamido-N-tert-butyl-2-[(3R)-1-(4-fluorobenzyl)pyrrolidin-3-yl]hex-5-enamide (210 mg, 0.52 mmol) in tetrahydrofuran (3 mL, 40 mmol) in a single portion. After stirring for 10 min at 0° C., the reaction was warmed to room temperature and stirred an additional 4 h. The mixture was diluted with aqueous sodium bicarbonate, extracted with DCM (3×50 mL), dried over Na2SO4, filtered and concentrated to give 2-acetamido-N-tert-butyl-2-((R)-1-(4-fluorobenzyl)pyrrolidin-3-yl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)hexanamide as a light orange oil that was used without further purification. ESI MS found for C29H47BFN3O4 m/z 532.3 (M+H)+

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