Mn(acac)_(3)促进烯醇酯与亚磷酸酯的自由基氧化偶联反应合成β-酮膦酸酯

Mn(acac)_(3)Promoted Radical Oxidative Coupling Reaction of Enol Esters with Phosphites to Synthesizeβ-Ketophosphonates

β-酮膦酸酯作为在天然产物和生物活性分子中广泛存在的结构骨架,在药物化学和有机转化等领域具有重要的合成价值.报道了一种Mn(acac)_(3)促进的芳基烯醇醋酸酯和烷基亚磷酸酯的氧化偶联反应,在温和且简单的条件下,实现了具有广泛官能团兼容性的β-酮膦酸酯的合成.反应步骤中涉及了锰氧化的膦自由基的生成以及自由基对不饱和键的加成过程.反应中所需的底物方便易得,且体系不需要任何酸或碱作为添加剂.最后进行了克级放大实验,进一步证明了这一策略在高效合成β-酮膦酸酯中的价值.

β-Ketophosphonates are widely found in the structural backbone of natural products and biologically active molecules,and they are of great synthetic value in medicinal chemistry,organic transformations and other fields.An Mn(acac)_(3)-promoted oxidative coupling reaction between aryl enol acetates and alkyl phosphites are reported,enabling the synthesis ofβ-ketophosphonates with broad functional group compatibility under mild and simple conditions.The generation of phosphorus radicals for manganese oxidation and the addition of radicals to unsaturated bonds were involved in the reaction.The substrates required for the reaction were readily available and the system did not require any acid or base as additives.Finally,a gram-scale experiment to further demonstrate the value of this strategy in the efficient synthesis ofβ-ketophosphonates was carried out.