Formal Deoxygenative Cross‐Coupling of Aldehydes to Ketones through α‐Haloboronates: A Route to Deoxygenative Hydroacylation of Aldehydes†

Comprehensive Summary Aldehydes are a kind of important synthons and reagents in organic synthesis. The efforts on transformations of aldehydes are highly rewarding and have always attracted considerable attention. Herein, a cross‐coupling of aldehydes with α‐haloboronates has been achieved under dual nickel/photoredox catalysis system. Considering the α‐haloboronates can be easily obtained from aldehydes with our deoxygenative difunctionalization of carbonyls (DODC) strategy, this protocol provides a formal deoxygenative cross‐coupling of aldehydes to one‐carbon‐prolonged ketone products. The mild conditions enabled good functional group tolerance and broad substrate applicability. The application of this method was presented via a tunable synthesis of two ketones with very similar skeletons from two same aldehydes.