Chemoselective Cobalt(I)-Catalyzed Cyclotrimerization of (Un)Symmetrical 1,3-Butadiynes for the Synthesis of 1,2,4-Regioisomers
作者:Sebastian M. Weber、Gerhard Hilt
DOI:10.1021/acs.orglett.9b01281
日期:2019.6.7
The cobalt(I)-catalyzed cyclotrimerization of (un)symmetrical 1,4-disubstituted 1,3-butadiynes is presented. In the case of unsymmetrical 1,3-butadiynes, this reaction can generate eight 1,2,4-substituted and four 1,3,5-substituted isomers. A single 1,2,4-substituted isomer was formed in excellent yields (up to 99%) and exclusive regioselectivities (>99:1) when symmetrical or a 1,3-butadiyne with an
提出了钴(I)催化的(非)对称的1,4-二取代的1,3-丁二炔的环三聚。在不对称的1,3-丁二炔的情况下,该反应可以产生8个1,2,4-取代的和4个1,3,5-取代的异构体。当对称或带有芳基或烷基取代基和三甲基甲硅烷基的1,3-丁二炔形成单一的1,2,4-取代的异构体时,产率极高(最高99%),排他区域选择性高(> 99:1)。应用。合成了接受多种官能团的大量产物。