Hydrochloric Acid → HCID 68869253, Verbindung

1.5 g of nitro derivative (19) prepared above and about 100 ml of methanol were introduced into a 200 ml autoclave (hydrogenator) equipped with a magnetic stirrer. The solution obtained was degassed with nitrogen. 0.4 g of palladium-on-charcoal (5% humidity, comprising 50% water) was added thereto. The reaction mixture was stirred, while flushing once with hydrogen, and hydrogen was then introduced to a pressure of about 5 bar. After reaction for 4 hours, the reactor was flushed with nitrogen and the reaction mixture was filtered quickly through Celite under a gentle pressure of nitrogen. The filtrate was recovered in a pre-cooled solution of methanol comprising about 3 equivalents of hydrogen chloride gas. It was rinsed several times with methanol under a stream of nitrogen. The solution thus obtained was concentrated and was then treated with ether. The product obtained, in the form of a pale pink paste, was stirred and then rinsed several times with acetonitrile and ether under nitrogen. 1.6 g of expected product (20) were isolated in the form of a slightly pink white powder.