Potassium Phosphate, Tribasic → 2'-(3,3-Dimethylbut-1-enyl)-7'-(pyrimidin-5-yl)-5h-spiro[oxazole-4,9'-xanthen]-2-amine

Participants

Reaction Conditions

Reaction Steps

A microwave vial was charged with (rac)-2′-Chloro-7′-(5-pyrimidinyl)spiro[1,3-oxazole-4,9′-xanthen]-2-amine (90 mg, 247 μmol), Pd2 dba3 (11 mg, 12 μmol), X-Phos (12 mg, 25 μmol), (E)-3,3-dimethylbut-1-enylboronic acid (63 mg, 493 μmol) and potassium phosphate (157 mg, 740 μmol). THF (2 mL) was added and the mixture was heated at 120° C. in microwave reactor for 2 hrs. The mixture was diluted with ethyl acetate and filtered through plug of Celite. After removal of the solvents the residue was purified by flash chromatography on silica gel (12 g Redi-Sep column, 20-100% DCM/MeOH/NH4OH 90:10:1 in DCM) to give 2′-(3,3-dimethylbut-1-enyl)-7′-(pyrimidin-5-yl)-5H-spiro[oxazole-4,9′-xanthen]-2-amine (65 mg, 64% yield). This product was hydrogenated at 1 atm of H2 in MeOH/EtOAc mixture using 10% palladium on carbon (53 mg, 49 μmol) for 60 hrs. The reaction mixture was filtered and concentrated in vacuo and was further purified by reverse-phase HPLC (10-90% CH3CN/H2O with 0.1% TFA). The fractions containing product were combined and dried overnight under high vacuum to give 2′-(3,3-dimethylbutyl)-7′-(pyrimidin-5-yl)-5H-spiro[oxazole-4,9′-xanthen]-2-amine as its TFA salt.

Provenance & Evidence