Abstract A ring enlargement reaction with methylamine gave new pyrido [2, 3-c]-, pyrido [3, 4- c]-and pyrido [3, 2-c] azocanone derivatives from cyclic β-oxo esters with a cyclopentapyridine skeleton and a 1, 4-diketone moiety. The starting materials for this ring transformation were either prepared from halogenopyridine carboxylates by Heck reaction and subsequent hydrogenation, or (halogenomethyl) pyridine carboxylates were ...
