1-(Benzyloxy)-4-bromo-2-fluorobenzene → (R)-4-(benzyloxy)-N-(2-(tert-butyldimethylsilyloxy)propyl)-3-fluoroaniline

関与物質

反応条件

反応手順

PdOAc2 (0.399 g, 1.78 mmol) and dicyclohexyl(2',4',6'-triisopropylbiphenyl-2-yl)phosphine (0.848 g, 1.78 mmol) were added in one portion to a degassed solution of 1-(benzyloxy)-4-bromo-2-fluorobenzene (5.00 g, 17.79 mmol), (R)-2-(tert- butyldimethylsilyloxy)propan-1-amine (3.37 g, 17.79 mmol) and cesium carbonate (8.69 g, 26.68 mmol) in toluene (120 mL) at 20°C in a microwave vial. The microwave vial was sealed and the reaction was heated to 120 °C for 10 hours in the microwave reactor and cooled to RT. **** Split into 5 x 20 ml mw vials such as in each was: PdOAc2 (0.080 g, 0.36 mmol) and dicyclohexyl(2',4',6'-triisopropylbiphenyl-2-yl)phosphine (0.170 g, 0.36 mmol) were added in one portion to a degassed solution of 1-(benzyloxy)-4-bromo-2-fluorobenzene (1.000 g, 3.56 mmol), Reactant 2 (1.143 g, 3.56 mmol) and cesium carbonate (1.739 g, 5.34 mmol) in toluene (20 mL) at 20°C in a microwave vial. The microwave vial was sealed and the reaction was heated to 120 °C for 10 hours in the microwave reactor and cooled to RT. **** The reaction was incomplete so the reaction was heated to 120 °C for 10 hours in the microwave reactor and cooled to RT. **** The reaction mixtures were combined and diluted with EtOAc (100 mL), and washed sequentially with water (100 mL) and saturated brine (100 mL). The organic layer was filtered and dried over Na2SO4. The filtrate was washed sequentially with water (100 mL), and saturated brine (100 mL). The organic layer was dried over MgSO4, filtered and evaporated to afford crude product. The crude product was purified by flash silica chromatography, elution gradient 0 to 30% EtOAc in isohexane. Pure fractions were evaporated to dryness to afford (R)-4-(benzyloxy)-N-(2-(tert- butyldimethylsilyloxy)propyl)-3-fluoroaniline (5.10 g, 73.6 %) as a orange oil.

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