N-Piperidinoethanol → 5-(1,3-Dioxolan-2-yl)-3-[2-(piperidin-1-yl)ethoxy]-1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-indazole

Participants

Reaction Steps

The title compound was prepared from 600 mg (1.344 mmol) 5-(1,3-dioxolan-2-yl)-3-iodo-1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-indazole (Example 6A) in analogy to the procedure described in Example 21A. The procedure was modified by using 5 equivalents of 2-(piperidin-1-yl)ethanol as the alcohol reactant and by switching to toluene as solvent. Instead of using microwave irradiation, the reaction mixture was refluxed for 5 days employing conventional heating. During this time, the same amounts of catalyst and ligand were added again on day 3. The crude product thus obtained was purified by chromatography on silica gel (cyclohexane/ethyl acetate gradient) to afford 244 mg (32% of th.) of the title compound.

Provenance & Evidence