Triphenylphosphine → 5-{[4-(tetrahydro-2H-pyran-2-yloxy)cyclohexyl]oxy}-1H-indazole

Beteiligte Stoffe

Reaktionsschritte

To a solution of the 1H-indazol-5-ol (250 mg) obtained in Reference Example 4 in tetrahydrofuran (15 ml) were added 4-(tetrahydro-2H-pyran-2-yloxy)cyclohexanol (373 mg, 1.86 mmol), triphenylphosphine (538 mg, 2.05 mmol) and dibenzyl azodicarboxylate (667 mg, 2.24 mmol) at 0° C. After 1 hour, the mixture thus obtained was heated to room temperature. After stirring overnight, the reaction solution was concentrated under reduced pressure, and a 1M-aqueous sodium hydroxide solution (50 ml) was added to the resulting residue, followed by extraction with chloroform (50 ml×2). The organic layer was washed with a saturated aqueous sodium chloride solution and then dried over anhydrous magnesium sulfate. The organic layer dried was concentrated under reduced pressure, and the resulting residue was purified by a silica gel column chromatography (eluent: hexane/ethyl acetate) to obtain 5-{[4-(tetrahydro-2H-pyran-2-yloxy)cyclohexyl]oxy}-1H-indazole (244 mg, 41%).

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