<i>tert</i>‐Amino effect at a coumarin and a 2‐quinolone system: Synthesis of 1,2 fused 5<i>H</i>‐chromeno[4,3‐<i>b</i>]pyridin‐5‐ones and a 6<i>H</i>‐benzo[<i>h</i>][1,6]naphthyridin‐5‐one
作者:Ivo C. Ivanov、Toma N. Glasnov、Ferdinand Belaj
DOI:10.1002/jhet.5570450120
日期:2008.1
4-chlorocoumarin-3-carbaldehyde (1a) or its N-methyl-2-quinolone analogue (1b) via subsequent Knoevenagel condensation and ring closure reaction known as the ‘tert-amino effect’. These are rare examples of the tert-amino effect occurring at 2-pyrone and 2-pyridone ring. An unusual intramolecular redox reaction of the iminium ion 6, reported earlier, most probably follows analogous mechanism as the tert-amino
一些新颖的1,2-稠合的5 H - chromeno [4,3- b ]吡啶-5-酮(5a,b)和6 H-苯并[ h ] [1,6]萘啶5-one(5c)由4-氯香豆素-3-甲醛(1a)或其N-甲基-2-喹诺酮类似物(1b)经随后的Knoevenagel缩合和称为“叔氨基效应”的闭环反应合成。这些是在2-吡喃酮和2-吡啶酮环上发生的叔氨基效应的罕见例子。亚胺离子6的异常分子内氧化还原反应,较早前报道,最有可能遵循类似的机制,导致5的叔氨基效应反应。