A reappraisal of the Ni-[(Benzylprolyl)amino]benzophenone complex in the synthesis of α,α-disubstituted amino acid derivatives
作者:Morag E. Watson、Craig Jamieson、Alan R. Kennedy、Andrew M. Mason
DOI:10.1016/j.tet.2019.130485
日期:2019.9
α-Disubstituted alkenyl amino acid derivatives (e.g. Fmoc-S5-OH) are valuable monomers in the construction of stapled peptide derivatives. Synthetic access to these is possible using the Ni-[(Benzylprolyl)amino]benzophenone (BPB) complex as a chiral auxiliary. We discuss a reappraisal of the use of this, and demonstrate that epimerisation of the proline α-centre occurs during formation of the complex, leading to
α,α-二取代的链烯基氨基酸衍生物(例如Fmoc-S 5 -OH)在构建短肽衍生物中是有价值的单体。使用Ni-[(苄基脯氨酰基)氨基]二苯甲酮(BPB)配合物作为手性助剂,可以合成这些化合物。我们讨论了对它的使用的重新评估,并证明脯氨酸α-中心的差向异构化发生在复合物的形成过程中,导致最终产物的对映异构体过量腐蚀。已经开发出改良的条件,以高对映体过量提供目标化合物。