steps from commercially available β,γ-unsaturated nitrile 9. Upon treatment with silver acetate under a range of reaction conditions, compound 27 underwent electrocyclic ring opening to give the corresponding π-allyl cation that was then trapped by the reaction solvent, chloride ion, and/or acetate ion, and so affording varying mixtures of the chlorocyclohexenes 28, 29, 30, and/or 31. Sequential treatment
在所检查的任何反应条件下,均未观察到由束缚
氨基甲酸酯捕获
中间体π-
烯丙基阳离子而产生的3型螺环化产物。相比之下,对更刚性的系统 38 进行类似处理,得到的化合物 39 结合了与强效神经毒素 perhydrohistrionicotoxin (2) 相关的 1-
氮杂螺[5.5]
十一烷骨架。