A remote δ methylene C(sp³)–H functionalization catalyzed by an organophosphine through an alkyne isomerization/conjugate addition cascade was discovered. No classical electron-withdrawing group is required to pre-activate the aryl alkyne, which will undergo isomerization to its corresponding diene under only 10 mol% of PMe₂Ph with a catalytic proton shuttle. The phosphoryl ylide was postulated as a key intermediate and different electrophiles were used to trap the vinylogous ylide that resulted in a large group of δ C(sp³)–H functionalized products (>60 examples, yields up to 99%) with good diastereoselectivity. Mechanistic studies were carried out and a catalytic cycle was proposed based on deuterium-labeling experiments. The conjugated polyene products were investigated for their fluorescence properties.

中文翻译：

---

通过有机膦催化的炔烃异构化实现的远程亚甲基C（sp3）–H功能化

通过炔烃异构化/共轭加成级联反应，发现了有机膦催化的远程δ亚甲基C（sp ³）-H官能化。不需要经典的吸电子基团来预活化芳基炔烃，该芳基炔烃将在仅10 mol％的PMe ₂ Ph催化下通过质子梭进行异构化为其相应的二烯。假定磷酰叶立德作为关键中间体，并且使用不同的亲电子试剂捕获乙烯基叶立德，从而产生了大量的δC（sp ³）–H功能化产物（> 60个实例，产率高达99％），具有非对映选择性。进行了机理研究，并基于氘标记实验提出了催化循环。研究了共轭多烯产物的荧光性质。