The development of new and efficient chiral extractant is of great concern in the field of chiral extraction. Axial chiral diphosphine, such as (S)-BINAP, has been proved to be effective chiral extractant. However, the stereoselectivity of chiral diphosphine with novel structure has been rarely investigated in chiral extraction. (S)-SDP, a famous spiro diphosphine used in asymmetric synthesis, was firstly employed to separate 4-Nitrophenylalanine enantiomers in this study. The influences of metal precursors, pH, extractant concentration and temperature on extraction were investigated. Separation factor (α), enantiomeric excess (ee) and performance factor (pf) were adopted to evaluate the efficiency of enantioseparation. (S)-SDP-Pd was suitable for separation of 4-Nitrophenylalanine enantiomers with the highest α of 3.32. L-4-Nitrophenylalanine was preferentially recognized by (S)-SDP-Pd in extraction. The extraction process was systematically optimized by response surface method. The optimum extraction condition was pH of 7.1, (S)-SDP-Pd concentration of 2.2 mmol/L and temperature of 14.0°C. At this optimum condition, the maximum pf was 0.08536. In addition, the possible chiral recognition mechanism was discussed.

在手性萃取领域中，新型和高效的手性萃取剂的开发受到极大关注。轴向手性二膦，如（S）-BINAP，已被证明是有效的手性萃取剂。然而，在手性萃取中很少研究具有新颖结构的手性二膦的立体选择性。（S）-SDP，一种用于不对称合成的著名的螺二膦，在本研究中首先用于分离4-硝基苯丙氨酸对映体。研究了金属前驱体，pH，萃取剂浓度和温度对萃取的影响。分离因子（α），对映体过量（ee）和性能因子（pf）被用来评估对映体分离的效率。（S）-SDP-Pd适合分离具有最高α为3.32的4-硝基苯丙氨酸对映体。在提取中，L-4-硝基苯丙氨酸优先被（S）-SDP-Pd识别。采用响应面法对提取工艺进行了系统优化。最佳提取条件为pH为7.1，（S）-SDP-Pd浓度为2.2 mmol / L，温度为14.0℃。在此最佳条件下，最大pf为0.08536。此外，讨论了可能的手性识别机制。