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

Participants

Reaction Conditions

Reaction Steps

In a microwave vial, potassium phosphate (0.307 g, 1.448 mmol), PdCl2(AmPhos)2 (0.026 g, 0.036 mmol), (S)-5-amino-2′-bromo-4′-fluoro-2,6-dihydrospiro[[1,4]oxazine-3,9′-xanthen]-7′-ol (0.183 g, 0.483 mmol), and 2-(3,6-dihydro-2H-pyran-4-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (0.147 g, 0.700 mmol) were suspended in dioxane (4 mL) and water (1.6 mL). Argon was blown through the vessel, which was sealed and heated by microwave at 120° C. for 30 min. The reaction was concentrated, and the residue was neutralized with ⅓ saturated aqueous NH4Cl (15 mL) and the aqueous phase was extracted with 5% MeOH-DCM (3×25 mL). The organics were combined, washed with dilute brine (7 mL), and concentrated to afford (S)-5-amino-2′-(3,6-dihydro-2H-pyran-4-yl)-4′-fluoro-2,6-dihydrospiro[[1,4]oxazine-3,9′-xanthen]-7′-ol which was used in the next step without further purification.

Provenance & Evidence