Synthetic and theoretical investigation on the one-pot halogenation of β-amino alcohols and nucleophilic ring opening of aziridinium ions
作者:Yunwei Chen、Xiang Sun、Ningjie Wu、Jingbai Li、Shengnan Jin、Yongliang Zhong、Zirui Liu、Andrey Rogachev、Hyun-Soon Chong
DOI:10.1039/c5ob01692d
日期:——
Aziridinium ions are useful reactive intermediates for the synthesis of enantiomerically enriched building blocks. However, N,N-dialkyl aziridinium ions are relatively underutilized in the synthesis of optically active molecules as compared to other three-membered ring cogeners, aziridines and epoxides. The characterization of both optically active aziridinium ions and secondary β-halo amines as the
iri啶鎓离子是用于合成对映体富集的结构单元的有用的反应性中间体。然而,与其他三元环同源热氮,氮丙啶和环氧化物相比,N,N-二烷基叠氮鎓离子在光学活性分子的合成中相对未被充分利用。几乎没有报道光学活性的叠氮鎓离子和仲β-卤代胺作为叠氮鎓离子的前体分子的表征,并且常常不清楚。在本文中,我们首次报道了旋光性叠氮鎓离子和仲β-卤代胺的制备以及实验和理论表征。旋光性次生N,NN,N-取代的丙氨醇通过卤化物在氮丙啶鎓离子的更受阻的碳上形成和开环而有效地合成了N-取代的β-卤代胺。通过NMR和计算分析对旋光性β-卤代胺和叠氮鎓离子进行了表征。通过X射线晶体学分析确认旋光性β-氯胺的结构。来自N,N的叠氮鎓离子-二苄基丙二醇仅在数小时内保持稳定,这对于分析NMR和光学活性而言足够长。使用DFT和高精度DLPNO-CCSD(T)方法,通过计算研究了卤化物对氮丙啶鎓离子的立体定向开环。氮丙啶鎓离子的高度区域