Kruger Hendrik G, Martins Frans J C, Viljoen Agatha M
School of Chemistry, University of Kwazulu-Natal, Durban 4001, South Africa.
J Org Chem. 2004 Jul 9;69(14):4863-6. doi: 10.1021/jo0357723.
The pentacycloundecane (PCU) cage structure resembles a perfect boat conformation, and for the first time unique lactam/lactone interconversions on the flagpole carbons of a cyclohexane boat structure are reported. The syntheses of a novel dihydroxy-PCU-delta-lactone and two novel N-substituted PCU-delta-lactams are reported. Hydrolysis of some of the PCU-delta-lactam compounds produced delta-lactones, and reaction of the lactones with ammonia or primary amines again produced delta-lactams. Reaction mechanisms to account for the unusual interconversion reactions induced by transannular interactions are proposed.
五环十一烷（PCU）笼状结构类似于完美的船式构象，并且首次报道了在环己烷船式结构的旗杆碳上独特的内酰胺/内酯相互转化。报道了一种新型二羟基-PCU-δ-内酯和两种新型N-取代的PCU-δ-内酰胺的合成。一些PCU-δ-内酰胺化合物水解生成δ-内酯，内酯与氨或伯胺反应又生成δ-内酰胺。提出了用于解释由跨环相互作用引起的异常相互转化反应的反应机理。
