通过Cp * Co III催化的CH烯基化/方向基团迁移序列,实现了高度原子经济和立体选择性的四取代α,β-不饱和酰胺的合成。通常在CH官能化后被除去的氨基甲酰基导向基团作为内部酰化剂起作用,并迁移到产物的烯烃部分上。使用Cp * Co III催化剂可实现导向基团的迁移,而相关的Cp * Rh III催化剂则不会促进迁移过程。将产物进一步转化为两种类型的三环化合物,其中一种具有荧光性质。
Ruthenium(II)-Catalyzed Redox-Neutral [3+2] Annulation of Indoles with Internal Alkynes via C–H Bond Activation: Accessing a Pyrroloindolone Scaffold
作者:Yanan Xie、Xiaowei Wu、Chunpu Li、Jiang Wang、Jian Li、Hong Liu
DOI:10.1021/acs.joc.7b00575
日期:2017.5.19
Ru(II)-catalyzed redox-neutral [3+2] annulation reactions of N-ethoxycarbamoyl indoles and internal alkynes via C–H bond activation are reported. This method features a broad internal alkyne scope, including various aryl/alkyl-, alkyl/alkyl-, and diaryl-substituted alkynes, good to excellent regioselectivity, diverse functional group tolerance, and mild reaction conditions. The N-ethoxycarbamoyl directing
economical and stereoselective synthesis of tetrasubstituted α,β‐unsaturated amides was achieved by a Cp*CoIII‐catalyzed C−H alkenylation/directing group migration sequence. A carbamoyl directing group, which is typically removed after C−H functionalization, worked as an internal acylating agent and migrated onto the alkene moiety of the product. The directing group migration was realized with the
通过Cp * Co III催化的CH烯基化/方向基团迁移序列,实现了高度原子经济和立体选择性的四取代α,β-不饱和酰胺的合成。通常在CH官能化后被除去的氨基甲酰基导向基团作为内部酰化剂起作用,并迁移到产物的烯烃部分上。使用Cp * Co III催化剂可实现导向基团的迁移,而相关的Cp * Rh III催化剂则不会促进迁移过程。将产物进一步转化为两种类型的三环化合物,其中一种具有荧光性质。
Pyrroloindolone Synthesis via a Cp*Co<sup>III</sup>-Catalyzed Redox-Neutral Directed C–H Alkenylation/Annulation Sequence
A unique synthetic utility of a Cp*Co(III) catalyst in comparison with related Cp*Rh(III) catalysts is described. A C2-selectiveindole alkenylation/annulation sequence proceeded smoothly with catalytic amount of a [Cp*Co(III)(C6H6)](PF6)2 complex and KOAc. Intramolecular addition of an alkenyl-Cp*Co species to a carbamoyl moiety gave pyrroloindolones in 58-89% yield in one pot. Clear difference was