N-Aminopyridinium salts generate nitrogen-centered radicals by means of photoredox catalysis. Herein, we report that they can be trapped by enol equivalents to give α-amino carbonyl compounds in excellent yields. The broad synthetic utility of this method is demonstrated by functionalization of ketones, aldehydes, esters enol equivalents, vinyl ethers, and 1,3-diketones without the need for prior conversion to enol derivatives. The developed method is easily scalable, offers broad substrate scope, high chemoselectivity.

Under UV light irradiation N,N-(diphenylamino)pyridinium salts generate nitrenium ions.Herein, we report that in the presence of a photoredox catalyst nitrogen-centered radicals form which can then react with enol equivalents to give α-amino carbonyl compounds in excellent yields. The broad synthetic utility of this method is demonstrated by functionalization of ketones, aldehydes, esters enol equivalents, vinyl ethers and 1,3-diketones without the need for prior conversion to enol derivatives. The developed method is easily scalable, offers broad substrate scope, high chemoselectivity, and mild conditions.

Despite the broad interest in organic compounds possessing a γ-aminocarbonyl motif, limited strategies for their synthesis have been reported. Herein, we describe a mild and efficient method for the site-selective amidation of unsaturated enones with electrophilic N-centered radicals as a key intermediate. The photocatalytic vinylogous reaction of dienolates with N-amino pyridinium salts affords γ-amido carbonyl compounds. This process is high-yielding, scalable, and tolerates a broad range of unsaturated α,β-unsaturated carbonyls, including biologically relevant compounds, as starting materials.T he concept of vinylogy, established by Fuson in 1935, 1 postulates that the influence of a functional group can be propagated through a conjugated system of unsaturated bonds. This phenomenon is particularly important for the functionalization of α,β-unsaturated carbonyl compounds, which are versatile starting materials in organic synthesis. 2−15 Typically, in vinylogous reactions, π-extended carbonyl derivatives of type I are transformed into dienolates II that contain two nucleophilic sites (Scheme 1). Consequently, the addition of electrophiles can occur at either α-position (III) or more remote γ-position