Regio‐ and Stereoselective 1,2‐Oxyhalogenation of Non‐Conjugated Alkynes via Directed Nucleopalladation: Catalytic Access to Tetrasubstituted Alkenes**
Palladium(II)-catalyzedregio- and stereoselective oxyhalogenation of unactivated internal alkynes is facilitated by a structurally tuned bidentate directing auxiliary, providing rapid access to tetrasubstituted alkenes that can be further diversified into valuable products.
钯 (II) 催化的未活化内部炔烃的区域选择性和立体选择性卤化作用通过结构调整的双齿定向助剂促进,提供快速获得四取代烯烃的途径,这些烯烃可以进一步多样化为有价值的产品。
Asymmetric Total Synthesis of (−)-Amphidinolide V through Effective Combinations of Catalytic Transformations
作者:Ivan Volchkov、Daesung Lee
DOI:10.1021/ja401717b
日期:2013.4.10
The synthesis features a base-catalyzed alkynyl silane alcoholysis/ring-closing enyne metathesis sequence for facile construction of a 1,3-diene motif. A diene RCM followed by a ring-contractive allylic transposition of cyclic silyl ethers was incorporated for the stereoselective installation of a functionalized 1,5-diene subunit. An efficient proline-mediated direct cross-aldol condensation of two
完成了 (-)-amphidinolide V 的不对称全合成。该合成具有碱催化的炔基硅烷醇解/闭环烯炔复分解序列,可轻松构建 1,3-二烯基序。引入二烯 RCM,然后是环状甲硅烷基醚的缩环烯丙基转座,用于立体选择性安装功能化的 1,5-二烯亚单元。两种高级醛中间体的高效脯氨酸介导的直接交叉羟醛缩合被用于构建关键的 α,β-不饱和环氧醛。这种全合成证明了金属催化转化在复杂分子合成中的威力。