Triphenylphosphine → Ethyl {3-[3-(4-hydroxyphenyl)-6-oxo-6H-pyridazin-1-ylmethyl]phenyl}carbamate

Participants

Reaction Conditions

Reaction Steps

5 g (17.3 mmol) of tert-butyl 4-(6-oxo-1,6-dihydropyridazin-3-yl)phenylcarboxylate, 5.08 g (26 mmol) of ethyl (3-hydroxymethylphenyl)carbamate and 6.8 g (26 mmol) of triphenylphosphine are dissolved in 400 ml of THF. Under a nitrogen atmosphere, the yellow solution is cooled to 0° C., 4.1 ml (26 mmol) of diethyl azodicarboxylate are slowly added dropwise, and the reaction mixture is stirred at room temperature for 20 h. The yellow suspension is evaporated to dryness. The residue is dissolved in 300 ml of dichloromethane, and 40 ml of trifluoroacetic acid are added. The reaction mixture is stirred at room temperature for 20 h, evaporated to dryness, and 100 ml of water, 200 ml of 1N NaOH and 100 ml of ethyl acetate are added to the viscous oil. A precipitate forms in the process, which is filtered off with suction, washed with water and dried in vacuo.

Provenance & Evidence