Pour 4-chloropyridine into distilled water, and excess of 6M NaOH is added to give pH 12. The organic phase is separated and extracted with four volumes of diethyl ether. The combined extracts are filtered through paper to remove water, and the solvent is evaporated. The dark brown residual liquid is kept under high vacuum [Vaidya & Mathias J Am Chem Soc 108 5514 1986]. It can be distilled, but readily darkens and is best kept as the hydrochloride [7379-35-3] M 150.1, m 163-165o(dec). [Beilstein 20/5 V 410.]
