Gold-Catalyzed Synthesis of Bicyclo[4.3.0]nonadiene Derivatives via Tandem 6-<i>endo-dig</i>/Nazarov Cyclization of 1,6-Allenynes
作者:Guan-You Lin、Chun-Yao Yang、Rai-Shung Liu
DOI:10.1021/jo0707939
日期:2007.8.31
Catalytic cyclization of 1,6-allenynes was achieved by AuPPh3SbF6 (5 mol %) in cold CH2Cl2 (0 °C, 0.5−4 h) to form bicyclo[4.3.0]nonadiene products; this cyclization proceeded more efficiently for a substrate bearing R = alkyl (yields >70%). We propose a reaction mechanism involving a 6-endo-dig cyclization of Au(I)-π-alkyne, followed by Nazarov cyclization.
1,6-炔烃的催化环化反应是通过AuPPh 3 SbF 6(5 mol%)在冷CH 2 Cl 2(0°C,0.5-4 h)中形成双环[4.3.0]壬二烯产物形成的。对于带有R =烷基的底物(收率> 70%),该环化反应更有效地进行。我们提出了一种反应机理,涉及Au(I)-π-炔烃的6-内挖-环化,然后是Nazarov环化。