Oxidized amines are ubiquitous in organic chemistry and frequently manifest themselves in complex synthesis campaigns: the Weinreb amide is an exemplar (Figure ). As key components in an impressive portfolio of enabling technologies, routes to generate and strategically leverage N-O bonds for structural pre-organization have been intensively pursued. This traceless tether features in a range of applications including target synthesis, drug delivery mechanisms, protein ubiquitylation and asymmetric catalysis. Prominent examples include the acyl nitroso Diels-Alder reaction (Figure ), and the nitrile oxide and oxime 1,3-dipolar cycloaddition 9 manifolds (Figure ). In contrast, methods to facilitate cleavage of the relatively labile N-O(Alkyl) bonds in Weinreb amides (~55-65 kcal/mol) are conspicuously underdeveloped and typically rely on disproportionately harsh conditions. This is noteworthy given the difficulties associated with selective monoalkylation and the attractiveness of reductive deprotection. The current suite of methods includes base-mediated elimination approaches 10 and metal reducing agents that enable single electron transfer processes (SET): Examples of the latter include samarium diiodide (N-OBn), 11 lithium (DTBB / NH3), 12 sodium, ruthenium (Zn-Cu) and titanium reagents (Figure ). A metal-free alternative has also been demonstrated using a super electron donor. Although metalbased SET methods constitute the vanguard of N-O bond cleavage platforms, this dominance must be reconciled with limited functional group compatibility and operational challenges. Elemental sulfur provides a milder alternative to the aforementioned reductants, but its use is confined to secondary amide derivatives and thus general solutions are required. 17 Photochemistry provides a versatile platform to initiate SET, enabling innovative, mild alternatives to be developed. A pertinent example is the N-O bond cleavage of N-alkoxyamides using a high energy mercury lamp and tributyltin hydride (N-OBn). Further advances in this field derive from photoredox catalysis-based methods, which mitigate the need for toxic reagents, thereby enabling the mild generation of open shell reactive species. A valuable contribution has been the introduction of very effective O-substituents (N-OAr, OAr = 2,4-dinitrophenol, N-OC(O)Ar, Ar = 3,5-bis trifluoromethyl phenyl) (Figure ): This enables N-O bond cleavage to be achieved upon irradiation with eosin Y in the presence of 1,4-cyclohexadiene, for HAT, using green LEDs or using an iridium photoredox catalyst. The resulting amidyl radicals may then be intercepted through sequential cyclization or arylation events.