Deoxygenative difunctionalization of carbonyls affords a straightforward and effective route to construct geminal dual functionalized motifs. However, the research in this field is very challenging due to the strong bond dissociation energies of the C−O double bond or the subsequently formed C−O bond. Herein, we report a highly efficient deoxygenative haloboration of aldehydes to generate secondary α-haloboronates. Meanwhile, the difficult-to-obtain tertiary α-haloboronates can be also readily prepared via the same strategy with ketones. Furthermore, enantioselective chloroboration of carbonyls was successfully achieved to give chiral secondary or tertiary α-chloroboronates, the important intermediates to access enantioenrich multisubstituted stereocenters. These versatile products can be surprisingly attained through this simple and mild process with remarkable substrate scope expansion and functional group tolerance. Additionally, these reactions can proceed well on large scales, giving more practical values in the application.

Substantial advances in enantioconvergent C(sp3)–C(sp3) bond formations have been made with nickel-catalyzed cross-coupling of racemic alkyl electrophiles with organometallic reagents or nickel-hydride-catalyzed hydrocarbonation of alkenes. Herein, we report an unprecedented enantioselective C(sp3)–C(sp3) reductive cross-coupling by the direct utilization of two different alkyl halides with dual nickel/photoredox catalysis system. This highly selective coupling of racemic α-chloroboronates and unactivated alkyl iodides furnishes chiral secondary alkyl boronic esters, which serve as useful and important intermediates in the realm of organic synthesis and enable a desirable protocol to fast construction of enantioenriched complex molecules.

Secondary α,α-dialkyl boronates are widely used due to their great versatility. Herein we report an unprecedented deoxygenative alkylboration of aldehydes, a facile method to access this type of products. A sequence of difunctionalization can be obtained smoothly from the readily available aldehydes in only two steps. This difunctionalization of aldehydes rather than conventional alkenes also opens new possibilities within the field.

Secondary α,α-dialkyl boronates are widely used due to their great versatility. Herein we report an unprecedented deoxygenative alkylboration of aldehydes, a facile method to access this type of products. A sequence of difunctionalization can be obtained smoothly from the readily available aldehydes in only two steps. This difunctionalization of aldehydes rather than conventional alkenes also opens new possibilities within the field.