Dehydrogenative [4 + 2] Cycloaddition of Formamides with Alkynes through Double C−H Activation

Formamides having 1-arylalkyl groups on nitrogen undergo an unprecedented dehydrogenative [4 + 2] cycloaddition reaction with alkynes via nickel/AlMe3 cooperative catalysis to give highly substituted dihydropyridone derivatives in good yields. Notably, the transformation proceeds through double functionalization of C(sp2)−H and C(sp3)−H bonds in the formamides.氮原子上连有1-芳基烷基的甲酰胺类化合物，可在镍/三甲基铝（AlMe3）协同催化下，与炔烃发生前所未有的脱氢型[4+2]环加成反应，并以优异收率得到高度取代的二氢吡啶酮类衍生物。值得注意的是，该转化过程实现了甲酰胺类化合物中C(sp²)-H与C(sp³)-H键的双重官能团化。