000170443 001__ 170443
000170443 005__ 20260420103355.0
000170443 0247_ $$2doi$$a10.1002/chem.70970
000170443 0248_ $$2sideral$$a148923
000170443 037__ $$aART-2026-148923
000170443 041__ $$aeng
000170443 100__ $$0(orcid)0000-0003-4249-6748$$aPedrón Laserna, Manuel$$uUniversidad de Zaragoza
000170443 245__ $$aWhen light challenges heat: mechanistic insights into a reaction competing with Cadogan Cyclisation in Nitro‐Perylenediimides
000170443 260__ $$c2026
000170443 5060_ $$aAccess copy available to the general public$$fUnrestricted
000170443 5203_ $$aVisible-light-driven transformations have emerged as powerful and sustainable tools in modern organic synthesis. However, the intrinsic photochemical reactivity of polycyclic aromatic hydrocarbons (PAHs) remains underexplored. Among π-conjugated chromophores, perylenediimides (PDIs) combine exceptional photostability, strong visible-light absorption, and rich redox properties, yet their light-induced chemical transformations are still poorly understood. Herein, we report an unprecedented divergence between thermal and photochemical reactivity in the reaction of bay-nitrated PDIs (PDI-NO2) with triphenylphosphine. While thermal activation promotes a classical Cadogan-type reductive cyclization to afford N-annulated PDI carbazole, visible-light irradiation redirects the reaction toward a previously unobserved pathway, yielding a bay-functionalized 1-(iminophosphorane)-12-hydroxy PDI derivative in excellent yield. Experimental studies reveal a strong wavelength dependence, with blue light dominating the photochemical transformation. Notably, the initial nitro-to-nitroso conversion is not phosphine-mediated but arises from the strong reducing power of photoexcited PDI-NO2. Combined experimental and theoretical investigations demonstrate that light irradiation reshapes the reaction landscape by enabling access to charge-transfer and π–π* excited states, involving the population of an asymmetric unoccupied orbital localized on the nitroso moiety, thereby unlocking a phosphine-addition pathway inaccessible under thermal conditions. These findings establish orbital-selective excitation as a general design principle for exploiting visible light to control reaction pathways in π-conjugated chromophores.
000170443 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttps://creativecommons.org/licenses/by/4.0/deed.es
000170443 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000170443 700__ $$aCiofini, Ilaria
000170443 700__ $$aHudhomme, Piétrick
000170443 7102_ $$12013$$2765$$aUniversidad de Zaragoza$$bDpto. Química Orgánica$$cÁrea Química Orgánica
000170443 773__ $$g(2026), e70970 [11 pp.]$$pChemistry (Weinh.)$$tChemistry (Weinheim)$$x0947-6539
000170443 8564_ $$s2202888$$uhttps://zaguan.unizar.es/record/170443/files/texto_completo.pdf$$yVersión publicada
000170443 8564_ $$s2508906$$uhttps://zaguan.unizar.es/record/170443/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000170443 909CO $$ooai:zaguan.unizar.es:170443$$particulos$$pdriver
000170443 951__ $$a2026-04-18-10:49:40
000170443 980__ $$aARTICLE