Potassium Phosphate, Tribasic → (S)-5-amino-2'-(5,6-dihydro-2H-pyran-3-yl)-4'-fluoro-2,6-dihydrospiro[[1,4]oxazine-3,9'-xanthen]-7'-ol

Participants

Reaction Conditions

Reaction Steps

In a microwave vial, the potassium phosphate (1.014 g, 4.78 mmol), PdCl2(AmPhos)2 (0.085 g, 0.119 mmol), (S)-5-amino-2′-bromo-4′-fluoro-2,6-dihydrospiro[[1,4]oxazine-3,9′-xanthen]-7′-ol (0.604 g, 1.593 mmol), and 2-(5,6-dihydro-2H-pyran-3-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (0.485 g, 2.310 mmol) were suspended in dioxane (6.5 mL) and water (2.5 mL). Argon gas was blown through the vessel, which was sealed and heated by microwave at 120° C. for 30 min. The mixture was concentrated. The residue was neutralized with half-saturated aqueous NH4Cl (35 mL). The aqueous phase was extracted with 5% MeOH/DCM (3×35 mL). The organics were combined, washed with dilute brine (15 mL), dried over sodium sulfate and concentrated to afford crude (S)-5-amino-2′-(5,6-dihydro-2H-pyran-3-yl)-4′-fluoro-2,6-dihydrospiro[[1,4]oxazine-3,9′-xanthen]-7′-ol which was used directly in the next step.

Provenance & Evidence