Scholarlink

<p>Development of contra-steric alkene hydrometallation method is one of the keys in branched product synthesis, especially when a bulky ligand steric environment is essential at other stages of the catalytic cycle. This study presents our efforts in this regard with broad scope using N-heterocyclic carbene (NHC), and establishes a chiral (NHC)Ni(II)-catalyzed intermolecular cross-hydroalkenylation system of enamine (alkenyl-carbamate/phthalimide) and <i>α</i>-olefin for the synthesis of highly substituted branched allylamines. A sterically adaptable chiral NHC-Ni(II) catalyst design with an open quadrant enhances interaction with the heteroatom on enamine, offering a precise chemo-, regio-, and enantioselective insertion control throughout the process in a mixture of olefins and allowing convergent synthesis. Besides, <i>α</i>-olefin serves as both terminal and internal 2-alkenyl reagents, yielding a 1,2,3-substituted allylamine by regio- and <i>E</i>-selective isomerization of the 1,2-disubstituted allylamine. Overall, the success of this alkene-based strategy addresses the intrinsic problems associated with alkyne- and alkenyl halide reagent-based synthesis, demonstrates good versatility and scope, and addresses the shortcomings of conceivable approaches based on rigid and sterically bulky NHCs.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

A contra-steric chemoselective hydrometallation strategy with bulky NHC for catalytic asymmetric branched allylamine synthesis

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年7月1日

查看全文
  • Weihao Chen,
  • Zhifeng Zhang,
  • Chun-Yu Ho

摘要

Development of contra-steric alkene hydrometallation method is one of the keys in branched product synthesis, especially when a bulky ligand steric environment is essential at other stages of the catalytic cycle. This study presents our efforts in this regard with broad scope using N-heterocyclic carbene (NHC), and establishes a chiral (NHC)Ni(II)-catalyzed intermolecular cross-hydroalkenylation system of enamine (alkenyl-carbamate/phthalimide) and α-olefin for the synthesis of highly substituted branched allylamines. A sterically adaptable chiral NHC-Ni(II) catalyst design with an open quadrant enhances interaction with the heteroatom on enamine, offering a precise chemo-, regio-, and enantioselective insertion control throughout the process in a mixture of olefins and allowing convergent synthesis. Besides, α-olefin serves as both terminal and internal 2-alkenyl reagents, yielding a 1,2,3-substituted allylamine by regio- and E-selective isomerization of the 1,2-disubstituted allylamine. Overall, the success of this alkene-based strategy addresses the intrinsic problems associated with alkyne- and alkenyl halide reagent-based synthesis, demonstrates good versatility and scope, and addresses the shortcomings of conceivable approaches based on rigid and sterically bulky NHCs.