3,4,5-Trichloropyridazine → 4-[(5,6-Dichloro-pyridazin-4-ylamino)-methyl]-piperidine-1-carboxylic acid benzyl ester

Participants

Reaction Steps

To a stirred solution of 3,4,5-trichloropyridazine (2.22 g, 12.08 mmol) and DIPEA (4.21 mL, 24.16 mmol) in IPA (25 mL) was added benzyl-4-(aminomethyl)piperidine-1-carboxylate (EXAMPLE 13, Step 1, 3.00 g, 12.08 mmol). The resulting reaction solution was stirred at rt for 5 h, then concentrated in vacuo. The residue was dissolved in CH2Cl2 (200 mL), washed with water (50 mL), dried over Na2SO4, filtered and concentrated. The crude product was purified by silica gel chromatography (1–7 (10% NH4OH in MeOH)/99–93 CH2Cl2) to give 4-[(5,6-dichloro-pyridazin-4-ylamino)-methyl]-piperidine-1-carboxylic acid benzyl ester.

Provenance & Evidence