Using Triethynylphosphine Ligands Bearing Bulky End Caps To Create a Holey Catalytic Environment: Application to Gold(I)-Catalyzed Alkyne Cyclizations
作者:Atsuko Ochida、Hideto Ito、Masaya Sawamura
DOI:10.1021/ja066800c
日期:2006.12.1
and catalytic uses of phosphinoalkynes bearing bulky end caps at the alkyne termini, that is, tris[(triarylsilyl)ethynyl]phosphines are reported. The most salient feature of the new phosphines is the holey molecular shape possessing a deep and large-scale metal-binding cavity. The holey phosphines displayed remarkable rate enhancement in the gold(I)-catalyzed six- and seven-membered ring forming cyclizations
报道了在炔末端带有庞大端盖的膦炔烃的合成、性质和催化用途,即三[(三芳基甲硅烷基)乙炔基]膦。新型膦最显着的特征是具有深而大尺度金属结合腔的多孔分子形状。多孔膦在金(I)催化的乙炔酮酯和 1,7-烯炔的六元和七元环形成环化中显示出显着的速率增强。有人提出,配体中的空腔迫使炔属化合物的亲核中心(烯醇或烯烃)靠近与金结合的炔烃,从而使闭环抗攻击成为可能。