β-Aminoketone als Schlüsselverbindungen zur Synthese von Pyridinen: Ein neuartiger, leistungsfähiger Zugang zu kondensierten Bi- und Terpyridinen

β-Amino Ketones as Key Intermediates in the Synthesis of Pyridines: A Novel and Efficient Route to Annelated Bi- and Terpyridines The hydrochlorides of β-amino ketones 1a – e (Mannich bases) are easily obtained starting compounds for a novel synthesis of pyridines. Condensation with the heteroaromatic ketones 8, 9, and 10 yields 5,6-dihydro-1,10-phenanthrolines 3a – d, 13 and 4,5-diazafluorenes 4a – d, which have not yet been described in literature. Symmetrical terpyridines 3e, 4e are formed in a one-step reaction of 8, 9 with dimethylmethylenammonium chloride in the presence of an ammonia source.