Cyclopentanol → 5-(cyclopentyloxy)-1H-indazole

Beteiligte Stoffe

Reaktionsschritte

Cyclopentanol (0.068 ml, 0.745 mmol), triphenylphosphine (221 mg, 0.820 mmol) and dibenzyl azodicarboxylate (267 mg, 0.895 mmol) were added at 0° C. to a solution of the 1H-indazol-5-ol (100 mg, 0.745 mmol) obtained in Reference Example 4 in tetrahydrofuran (6 ml). After 30 minutes, 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 (4 ml) and chloroform (3 ml) were added to the resulting residue. After removing the aqueous layer, water (2 ml) was added to the residue. The aqueous layer was removed and the organic layer was dried over anhydrous magnesium sulfate. The organic layer dried was concentrated and the resulting residue was purified by a silica gel column chromatography (eluent: chloroform/methanol, hexane/ethyl acetate) to obtain 5-(cyclopentyloxy)-1H-indazole (24 mg, 16%).

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