Harnessing the ambiphilicity of silyl nitronates in a catalytic asymmetric approach to aliphatic β3-amino acids
作者:Sayantani Das、Benjamin Mitschke、Chandra Kanta De、Ingolf Harden、Giovanni Bistoni、Benjamin List
DOI:10.1038/s41929-021-00714-x
日期:——
bond-forming reactions. In contrast, the corresponding silyl nitronates are ambiphilic and react, at the same carbon atom, with both electrophiles and nucleophiles. However, while their nucleophilicity has been well exploited in catalytic enantioselective reactions with imines and aldehydes, utilizing the electrophilicity of silyl nitronates in asymmetric synthesis has remained elusive. Here we report the facile
硝酸根阴离子是通过对相应的硝基烷烃进行α-去质子化而正式产生的,在许多碳-碳键形成反应中是高度亲核且用途广泛的中间体。相反,相应的硝酸甲硅烷基酯是两亲的,并且在相同的碳原子上与亲电试剂和亲核试剂发生反应。然而,虽然它们的亲核性在与亚胺和醛的催化对映选择性反应中得到了很好的利用,但在不对称合成中利用硝酸甲硅烷基酯的亲电性仍然难以捉摸。在这里,我们报告了在高路易斯酸性和受限的亚氨基二亚磷酸甲硅烷基甲硅烷基催化剂催化下,容易获得的硝基甲硅烷基酯与甲硅烷基乙烯酮缩醛的简便、高效和普遍的反应性。该反应的产物,即所谓的亚硝基缩醛,N -Boc-β 3 -氨基酸酯一步完成。