Access to multifunctional hydrazones of relevance to dysiherbaine synthesis studies is described. Subsequent radical cyclizations of multifunctional hydrazones via a Si- and C-linked tethering strategy are shown to function effectively in 6-exo fashion. Conformational constraints are proposed to play a key role in suppressing unproductive premature reduction pathways. The stereochemical outcomes suggest
描述了获得与dysiherbaine 合成研究相关的多功能腙。随后通过 Si 和 C 连接的束缚策略对多功能腙进行的自由基环化显示出以 6-exo 方式有效发挥作用。构象约束被提议在抑制非生产性过早还原途径方面发挥关键作用。立体
化学结果表明,与通常的 Beckwith 相比,最小化相邻 C=N 和 CO 键之间的偶极排斥有利于 C(alpha)-C(=N) 二面角将 C=N 键轴向置于椅子状过渡态内-Houk 模型。