Chiral Phosphate in Rhodium-Catalyzed Asymmetric [2+2+2] Cycloaddition: Ligand, Counterion, or Both?
作者:Marion Barbazanges、Elsa Caytan、Denis Lesage、Corinne Aubert、Louis Fensterbank、Vincent Gandon、Cyril Ollivier
DOI:10.1002/chem.201601188
日期:2016.6.13
Investigations based on NMR spectroscopy, mass spectrometry, and DFT calculations shed light on the metallic species generated in the rhodium‐catalyzed asymmetric [2+2+2] cycloaddition reaction between diynes and isocyanates with the chiral phosphate TRIP. The catalytic mixture comprising [Rh(cod)Cl}2], 1,4‐diphenylphosphinobutane (dppb), and Ag(S)‐TRIP actually gives rise to two species, both having
基于NMR光谱,质谱和DFT计算的研究揭示了手性磷酸盐TRIP在二炔和异氰酸酯之间铑催化的不对称[2 + 2 + 2]环加成反应中生成的金属物种。包含[Rh(cod)Cl} 2 ],1,4-二苯基膦基丁烷(dppb )和Ag(S)-TRIP的催化混合物实际上产生了两种,均对立体选择性有影响。一种是铑(I)络合物,其中TRIP是弱配位的抗衡离子,而另一种是双金属Rh / Ag络合物,其中TRIP是强配位的X型配体。