The synthesis and transformations of substituted 2-hydroxy-3 dimethylaminopropenoates. The preparation of condensed 3-hydroxypyran-2-ones

Article abstract of DOI:10.1016/S0040-4020(98)00534-1

A convenient synthesis of substituted 2-bydroxy-3- dimethylaminopropenoates is reported. They react with cyclic 1,3-diketones, with aromatic and heteroaromatic hydroxy compounds to afford the corresponding 3-substituted hydroxytetrahydro-2H-1-benzopyran-2-ones, benzo- and naphthopyran-2-ones and azolo- and azinopyran-2-ones, respectively. Catalytic debenzylation of 3-benzyloxy substituted fused pyran-2-ones gives free 3-hydroxy derivatives.