Synthesis of Spirolactams and Fused Bicyclic Lactams via Acid-Promoted Cyclolactamization of (Ethynyl(tosyl)amino)methyl-Tethered Cyclohex-2-enols
作者:Po-Ting Tung、Chang-Zhi Zhong、Tzu-Chiang Chien、Ming-Chang P. Yeh
DOI:10.1021/acs.joc.7b02158
日期:2017.11.3
keteniminium–allylic carbocation intermediate. Hydration of the keteniminium ion, followed by attack of the resulting enolate onto the tethered allylic carbocation, provided the spirolactam ring skeleton. This strategy could also be employed in the synthesis of fused bicyclic lactams from BF3·OEt2-assisted cyclolactamization of TBS-protected 2-(ethynyl(tosyl)amino)methylcyclohex-2-enols.
描述了一种简单的合成方法,该方法由TfOH催化的带有环链的(芳基乙炔基(甲苯磺酰基)氨基)甲基的环己-2-烯醇的螺内酰胺化反应来构建螺内酰胺骨架。反应通过酮亚胺基-烯丙基碳正离子中间体进行。水合酮亚胺离子,然后将所得烯醇化物攻击到束缚的烯丙基碳正离子上,提供了螺内酰胺环骨架。该策略也可用于由BF 3 ·OEt 2辅助的TBS保护的2-(乙炔基(甲苯磺酰基)氨基)甲基环己-2-烯醇的环内酰胺化合成稠合双环内酰胺。