Rhodium-Catalyzed Asymmetric Cyclization/Hydroboration of 1,6-Enynes
作者:Robert E. Kinder、Ross A. Widenhoefer
DOI:10.1021/ol052986t
日期:2006.5.1
[reaction: see text] Reaction of enyne 1 with catecholborane catalyzed by a 1:1 mixture of [Rh(COD)(2)](+)SbF(6)(-) and (S)-BINAP (5 mol %) followed by Pd-catalyzed arylation with p-IC(6)H(4)CF(3) gave benzylidenecyclopentane 5 in 65% yield with 88% ee. Rhodium-catalyzed asymmetric cyclization/hydroboration followed either by Pd-catalyzed arylation or by oxidation was applied to the synthesis of a
Chiral Cationic Cp<sup>x</sup>Ru(II) Complexes for Enantioselective Yne-Enone Cyclizations
作者:David Kossler、Nicolai Cramer
DOI:10.1021/jacs.5b08232
日期:2015.10.7
cyclopentadienyl (Cp) group is a ligand of great importance for many transition-metal complexes used in catalysis. Cationic CpRu(II) complexes with three free coordination sites are highly versatile catalysts for many atom-economic transformations. We report the synthesis of a family of Cp(x)Ru(II) complexes with chiral Cp ligands keeping the maximum number of available coordination sites. The cationic
环戊二烯基 (Cp) 基团是许多用于催化的过渡金属配合物的重要配体。具有三个自由配位点的阳离子 CpRu(II) 配合物是用于许多原子经济转化的高度通用的催化剂。我们报告了具有手性 Cp 配体的 Cp(x)Ru(II) 复合物家族的合成,可保持最大数量的可用协调位点。阳离子成员是通过正式的异狄尔斯-阿尔德反应进行炔-烯酮环化的有效且选择性的催化剂。转化在 -20 °C 下进行 <1 小时,并提供高达 99:1 er 的吡喃。不饱和酯或 Weinreb-酰胺底物直接产生环烯醚萜骨架。