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.氮原子上带有1-芳烷基的甲酰胺，在镍/三甲基铝（AlMe3）协同催化下，可与炔烃发生前所未有的脱氢[4+2]环加成反应，生成高度取代的二氢吡啶酮衍生物且收率良好。值得注意的是，该转化实现了甲酰胺中C(sp2)-H与C(sp3)-H键的双重官能化。