作者:Frank Maier、Oliver Trapp
DOI:10.1002/chir.22125
日期:2013.2
revealing that the activation barrier of these 5,5’‐substituted BIPHEP ligands ranges in a narrow band between 87.8 and 93.0 kJ mol–1, making them highly attractive as deracemizable dynamic chiral ligands in asymmetric catalysis. Interestingly, the activation parameters are highly influenced by a hydroxyl or methoxy group in the 5,5’‐position of the BIPHEP ligands. Chirality 25:126–132, 2013. © 2012 Wiley
我们通过对映选择性动态高效液相色谱(DHPLC)研究了5,5'-取代的Tropos BIPHEP配体(2,2'-bis(diphenylphosphino)-biphenyls)的立体动力学,以阐明取代模式和电子对电子的影响。取代基(甲基,甲氧基和羟基)。由随温度变化的动态HPLC测量的激活参数Δ ģ ╪,Δ ħ ╪,和Δ小号╪可以高精度地确定,表明的活化能垒这些5,5'-取代的配体BIPHEP在范围之间的窄带87.8和93.0 kJ mol –1,使其在不对称催化中作为可脱硝的动态手性配体具有很高的吸引力。有趣的是,活化参数受BIPHEP配体5,5'-位置上的羟基或甲氧基的影响很大。手性25:126–132,2013年。分级为4 +©2012 Wiley Periodicals,Inc.