Stereoselective Coordination to Chiral Matrices. Cobalt(III). Chemistry of Simple Facially Coordinating Chiral Triamines
作者:Peter Comba、Aldo Hörmann、Lisandra L. Martin、Luc Zipper
DOI:10.1002/hlca.19900730413
日期:1990.6.20
X: NH3, OH2, OH−). Equilibration of Co(III) complexes was achieved by oxygenation of aqueous solutions of Co(II) salts in presence of the ligands. Quantitative isomer distribution was investigated with HPLC, and quantitative analysis of the enantiomeric excess (ee) of the racemic substrate (present in a two-fold excess) was studied, after chromatographical recovery, by 1H-NMR analysis of its Mosher-acid
与金属离子配位的手性配体对外消旋底物的其他配位具有选择性。将实验确定的[Co(L 3)2 ] 3+和[Co(L 3)(L 2)(X)] n +的平衡分布与基于应变能最小化的计算数据进行比较(L 3:阱=丙烷) -1,2,3-三胺; 1,2,4-trab =丁烷-1,2,4-三胺; 1,2,3-trab =丁烷-1,2,3-三胺; 1,3,4 -trpe =戊烷-1,3,4-三胺; 1,3,4-tmeb = 2-甲基丁烷-1,3,4-三胺; 1,2,4-trpe =戊烷-1,2,4-三胺; L 2:en =乙烷-1,2-二胺; pn =丙烷-1,2-二胺; X:NH 3,OH 2,OH−)。Co(III)配合物的平衡是通过在配体存在下氧化Co(II)盐的水溶液来实现的。用HPLC研究了异构体的定量分布,并在色谱回收后通过1 H-NMR分析了其Mosher-酸衍生物,对外消旋底物的对映体过量(