The behavior of the tricyclic compounds 3, 4, and 5 towards reductive systems is described. The [4 + 2] cycloadduct 3, when reduced by NaBH4/CeCl3 · 6 H2O led to the isolation of the nortricyclenic compound 8 whereas the cycloadduct 4 provided the analog 9. The reduction of norbornenequinone 5 gave the aromatized compound 10 when performed by sodium dithionite or by NaBH4/CeCl3 · 6 H2O. The structure and stereochemistry of the hydroxyl group in the compound 8 was determined by NMR and confirmed by X-ray analysis. Also, some mechanistic considerations concerning the formation of the compounds 8 and 9 are presented.
本文介绍了
三环化合物 3、4 和 5 在还原体系中的表现。当 NaBH4/
CeCl3 - 6
H2O 还原[4+2]环加载产物 3 时,可分离出去
三环化合物 8,而环加载产物 4 则提供了类似物 9。用
连二亚硫酸钠或 NaBH4/ - 6 还原
降冰片烯醌 5 可以得到芳香化的化合物 10。通过核磁共振确定了化合物 8 中羟基的结构和立体
化学性质,并通过 X 射线分析予以证实。此外,还介绍了有关化合物 8 和 9 形成的一些机理。