A new approach to cyclic hydroxamic acids: intramolecular cyclization of N-benzyloxy carbamates with carbon nucleophiles
作者:Yuan Liu、Hollie K. Jacobs、Aravamudan S. Gopalan
DOI:10.1016/j.tet.2011.01.073
日期:2011.3
moderate yields. The sulfone intermediates 3 from this study can be alkylated while the corresponding phosphonates have been shown to undergo HWE reaction. The α,β-unsaturated synthon, 8, prepared by thermal elimination of sulfoxide 3m, undergoes Michael addition with secondary amines. The usefulness of this approach to prepare polydentate chelators has been demonstrated by the synthesis of bis cyclic hydroxamic
N-烷基-N-苄氧基氨基甲酸酯2与各种碳亲核试剂进行轻松的分子内环化,得到官能化的五元和六元受保护环状异羟肟酸3,收率良好至极好。该方法可以扩展到以中等产率制备七元环异羟肟酸。本研究中的砜中间体3可以被烷基化,而相应的膦酸酯已被证明可以进行 HWE 反应。α,β-不饱和合成子, 8 , 亚砜3m热消去制备, 与仲胺发生迈克尔加成。这种方法中,以制备多齿螯合剂的实用性已经通过双环状异羟肟酸的合成方法证实12,14,和15。