A convenient synthesis of benzylic phosphonates and 2,3-dihydrobenzo[d][1,2]oxaphosphole 2-oxides substituted at the aromatic ring, as well as their precursors, 2-hydroxybenzylic alcohols, from the derivatives of salicylic aldehyde, salicylic acid, and 2-hydroxyacetophenone bearing an additional hydroxy or methoxy group at the para position of the aromatic ring was developed. For the first time, the possibility of selective demethylation of the methoxy group positioned ortho to the methylene phosphonate fragment with retention of the methoxy group at the para position was shown.

中文翻译：

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基于取代的 2-羟基苯甲醇的无环和环状膦酸酯的合成

从水杨醛、水杨酸的衍生物中方便地合成苄基膦酸酯和芳环取代的 2,3-二氢苯并[d][1,2]氧杂磷酰 2-氧化物，以及它们的前体，2-羟基苄醇和 2-羟基苯乙酮在芳环的对位带有一个额外的羟基或甲氧基。首次显示了选择性去甲基化位于亚甲基膦酸酯片段邻位的甲氧基的可能性，而甲氧基保留在对位。