4-Nitrobenzoic Acid → HCID 86657804, compound

Participants

Reaction Steps

To a stirred mixture of (±)-cis-3-[6-butyl-5-(4-cyclohexyloxy-phenyl)-pyridazin-3-yloxymethyl]-4-hydroxy-piperidine-1-carboxylic acid tert-butyl ester (Example 43, 1.18 mmol, 0.64 g), PPh3 (1.43 mmol, 0.375 g) and p-nitrobenzoic acid (1.5 mmol, 0.251 g) in anhydrous THF (15 mL) at −60° C. was added DIAD (1.43 mmol. 0.289 mL) over 10 min. The stirring was continued and let the reaction slowly attain room temperature over 3 h. The reaction mixture was diluted with ether (300 mL), washed with water (100 mL) followed by saturated sodium bicarbonate (100 mL). The organic layer was dried, filtered and concentrated under reduced pressure. The residue was purified by flash silica gel flash column chromatography by eluting with 20% ethyl acetate in hexanes to provide (±)-trans-3-[6-butyl-5-(4-cyclohexyloxy-phenyl)-pyridazin-3-yloxymethyl]-4-(4-nitro-benzoyloxy)-piperidine-1-carboxylic acid tert-butyl ester (0.63 g).

Provenance & Evidence