Ethylenediamine → Lazabemide

Beteiligte Stoffe

Reaktionsschritte

The amidation of 5 g (33.8 mmol) of 2,5-dichloropyridine in the presence of 12.1 g (202 mmol) of ethylenediamine, 8.8 mg of palladium-dichloro-bis(acetonitrile) and 21 mg of 1,3-bis(diphenylphosphino)propane is carried out at 110° in a manner analogous to Example 1. After the addition of 1.91 g (35.5 mmol) of sodium methylate and evaporation of the reaction mixture there are obtained, by extraction with 3N hydrochloric acid and subsequent basification of the acidic-aqueous solution, 5.05 g (75%) of N-(2-aminoethyl)-5-chloropyridine-2-carboxamide; content according to HPLC: 98.2 wt. %, content of N,N'-ethylene-bis(5-chloro-2-pyridinecarboxamide): <1% (GC). Conversion of the free base with hydrogen chloride in methanol into the hydrochloride and crystallization from methanol/ether yields N-(2-aminoethyl)-5-chloropyridine-2-carboxamide hydrochloride as white crystals, m.p. 191°-195°.

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