The development of alkyne transformations extending from non-catalytic, transition-metal or acid catalyzed additions and cyclizations, to metathesis, metalations, and radical addition reactions, has been a longstanding and one of the essential research objectives in organic synthesis. Conceptually, a single-electron oxidation event of carbon-carbon triple bond could lead to the generation of an alkyne radical cation, which presents a synthetically attractive intermediate. Such a species might offer a new range of versatile reactivities complementary to the current alkyne chemistry (Scheme 1a), for example, a new approach for alkyne functionalization. However, reported methods for alkyne radical cation generation are limited to γ-irradiation or the use of strongly oxidizing conditions; and its catalytically generation and applications in synthetically meaningful reactions still remain scarce. It is surmised that such challenge is a result of two major reasons: 1) general alkynes, as known, typically possessing high oxidation potential (Scheme 1b, over + 2.0 V), require potent oxidants to achieve the single-electron oxidation, which limits the synthetic application; 2) the exceptionally high reactivity of alkyne cation radicals makes them challenging intermediates for the development of controllable and selective transformations. Recently, our group developed a novel photocatalytic strategy for the generation of reactive and controllable -oxypyridinium radical through mild visible-light photoredox catalyzed single-electron oxidation of an alkyne/pyridine N-oxide system. During these studies, it was found that ynamides, subgroups of alkynes, exhibited significantly lower oxidation potentials than aliphatic and aryl alkynes (Scheme 1b, Figure and). In this context, we envisaged that ynamide could serve as an ideal substrate for alkyne radical cation generation by single-electron oxidation under mild reaction conditions, such as using visible-light photoredox catalyst. We rationalize that the strong polarization of ynamide introduced by the electron-donating ability Scheme 1. Single electron oxidation of alkynes and their redox potentials.