作者:Daniel Dauzonne、Cyrille Grandjean
DOI:10.1055/s-1992-26198
日期:——
2-Aryl-3-nitro-4H-1-benzopyran-4-ones (or 3-nitroflavones) 3 are conveniently prepared in good yields using a two-step approach starting from 2-aryl-3-chloro-3,4-dihydro-4-hydroxy-3-nitro-2H-1-benzopyrans 1. A general synthesis of the novel 2-aryl-3-chloro-2,3-dihydro-3-nitro-4H-1-benzopyran-4-ones 2 employed as intermediates in the procedure is described.
2-Aryl-3-nitro-4H-1-benzopyran-4-ones (or 3-nitroflavones) 3 are conveniently prepared in good yields using a two-step approach starting from 2-aryl-3-chloro-3,4-dihydro-4-hydroxy-3-nitro-2H-1-benzopyrans 1. A general synthesis of the novel 2-aryl-3-chloro-2,3-dihydro-3-nitro-4H-1-benzopyran-4-ones 2 employed as intermediates in the procedure is described.