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报道了钌催化末端炔丙醇经亚丙二烯基卡宾中间体氧化产生亚甲基烯酮合成α,β-不饱和羧酸衍生物的高效方法.机理研究实验表明,催化剂CpRuC1(PPh3)2/NaBPh4和末端炔丙醇反应产生的钌亚丙二烯基卡宾与吡啶氧化物发生氧转移,生成高活性的亚甲基烯酮中间体,再发生亲核加成得到α,β-不饱和产物.该反应提供了一个机理上完全不同于传统方法的合成α,β-不饱和羧酸衍生物的新策略,是炔丙醇催化转化的一种新颖方法,也是金属亚丙二烯基催化的一种新途径.“,”A ruthenium-catalyzed oxygenative transformation of terminal propargyl alcohols to metheyleneketenes via al-lenylidene intermediates has been developed for the synthesis of a variety of α,β-unsaturated carboxylic acid derivatives.Mechanistic study experiments disclosed that oxygen transfer from pyridine-N-oxide to ruthenium allenylidene generated from the reaction of catalyst CpRuCI(PPh3)2/NaBPh4 with terminal propargyl alcohol resulted in the formation of reactive meth-yleneketene intermediate,which was trapped into nucleophilic addition reactions to afford α,β-unsaturated product.This reac-tion offers an attractive complementary strategy to the traditional approach for the synthesis of this class of unsaturated com-pounds,but in a distinct mechanism,which provides a novel method for the transformation of propargylic alcohols.The metal allenylidene-to-methyleneketene transformation also represents a new mechanistic modality for metal allenylidene-mediated catalysis.