Direct synthesis of ketones from aldehydes features high atom- and step-economy. Yet, the coupling of aldehydes with unactivated alkyl C(sp³)-H remains challenging. Herein, we develop the synthesis of ketones from aldehydes via alkyl C(sp³)-H functionalization under photoredox cooperative NHC/Pd catalysis. The two-component reaction of iodomethylsilyl alkyl ether with aldehydes gave a variety of β-, γ- and δ-silyloxylketones via 1,n-HAT (n = 5, 6, 7) of silylmethyl radicals to generate secondary or tertiary alkyl radicals and following coupling with ketyl radicals from aldehydes under photoredox NHC catalysis. The three-component reaction with the addition of styrenes gave the corresponding ε-hydroxylketones via the generation of benzylic radicals by the addition of alkyl radicals to styrenes and following coupling with ketyl radicals. This work demonstrates the generation of ketyl radical and alkyl radical under the photoredox cooperative NHC/Pd catalysis, and provides two and three component reactions for the synthesis of ketones from aldehydes with alkyl C(sp³)-H functionalization. The synthetic potential of this protocol was also further illustrated by the late-stage functionalization of natural products.

由醛直接合成酮具有较高的原子经济性和步骤经济性。^{然而，醛与未活化的烷基 C(sp 3} )-H的偶联仍然具有挑战性。在此，我们开发了在光氧化还原协同 NHC/Pd 催化下通过烷基 C(sp ^{3 )-H 官能化从醛合成酮的方法。}碘甲基甲硅烷基烷基醚与醛的双组分反应通过 1,n-HAT ( n = 5, 6, 7) 的甲硅烷基甲基自由基生成仲或叔烷基自由基，并在光氧化还原 NHC 催化下与醛中的羰基自由基偶联。苯乙烯加成的三组分反应通过将烷基加成到苯乙烯上并随后与羰基偶联而产生苄基，从而产生相应的ε-羟基酮。该工作演示了在光氧化还原协同NHC/Pd催化下生成羰基自由基和烷基自由基，并为从带有烷基C(sp 3 )-H官能化的醛合成酮提供了二组分和三组分^反应。天然产物的后期功能化也进一步说明了该方案的合成潜力。