Semihollow triethynylphosphanes were synthesized and employed as ligands in the gold‐catalyzed 8‐exo‐dig cyclization of acetylene‐tethered silyl enol ethers to obtain eight‐membered‐ring carbocycles (see scheme). The gold–phosphane catalysts promoted either the annulation toward bicyclic structures or the cyclization of acyclic molecules to form nonfused carbocycles. Tf=Trifluoromethylsulfonyl.
Semihollow triethynylphosphanes合成和用作在配位体的
金催化8-外-Dig的环化
乙炔拴甲
硅烷基
烯醇醚,得到八元环的
碳环(参见方案)。
金-膦
催化剂促进了向双环结构的环化或促进了无环分子的环化,从而形成了非稠合的
碳环。Tf =三
氟甲基磺酰基。