Triphenylphosphine → Di-tert-butyl (3-(3-(4-((pyridin-2-yloxy)methyl)benzyl)isoxazol-5-yl)pyridin-2-yl)imidodicarbonate

Participants

Reaction Conditions

Reaction Steps

Under a nitrogen atmosphere, to a mixture of (5-{2-[bis(tert-butoxycarbonyl)amino]pyridin-3-yl}isoxazol-3-yl)methyl 4-methylbenzenesulfonate (82 mg, 0.15 mmol), {4-[(pyridin-2-yloxy)methyl]phenyl}boronic acid (34 mg, 0.15 mmol), potassium phosphate (35 mg, 0.17 mmol), triphenylphosphine (7.9 mg, 0.03 mmol), and toluene (1.0 mL) was added palladium acetate (1.7 mg, 5 mol %), which was stirred for 16 hours at 90° C. After cooling, ethyl acetate and water were added thereto, and the mixture was transferred to a separatory funnel and separated. The organic layer was washed with saturated sodium chloride solution and then dried over anhydrous magnesium sulfate, the solvent was evaporated under a reduced pressure. The residue was purified by silica gel column chromatography, so as to obtain a mixture of the titled compound, (5-{2-[bis(tert-butoxycarbonyl)amino]pyridin-3-yl}isoxazol-3-yl)methyl 4-methyl benzenesulfonate, and di-tert-butyl [3-(3-methylisoxazol-5-yl)pyridin-2-yl]imidodicarbonate (63 mg:molar ratio of 59:33:8), as a pale yellow oil.

Provenance & Evidence