Work

1‐Nitro‐7‐Donor Functionalized Perylenediimides: Synthesis, Photophysical Properties, Redox Behavior, and Nanosecond Transient Studies

Year: 2026

Type: article

Abstract: ABSTRACT A set of push–pull donor substituted nitro‐perylenediimide (NO 2 ‐PDI)‐based derivatives NPDI 1 – 4 were designed and synthesized via nitration reaction of the mono‐brominated‐PDI (Br‐PDI) followed by Pd(II)‐catalyzed Sonogashira cross–coupling reaction in good yields. The nitro group was substituted at the bay position of the PDI‐NO 2 , and a variety of donors (phenothiazine (PTZ), carbazole(CBZ), and N,N ‐dimethylaniline(NND) were functionalized on the other bay side. The photophysical, electrochemical, spectroelectrochemical, computational calculations, and nanosecond transient absorption (ns‐TA) studies were performed on the synthesized derivatives NPDI 1 – 4 . The photophysical properties of NPDI 2 – 4 exhibit absorption in the NIR region due to strong push–pull interaction, resulting in stabilized LUMO energy levels to a greater extent. The electrochemical study reveals that the redox potentials of NPDI 1 – 4 derivatives shifted toward the anodic side due to the strong electron‐withdrawing nature of the NO 2 ‐PDI moiety. The spectroelectrochemical analysis revealed the absorption spectra shifted toward the bathochromic region during the reduction cycles, while a hypochromic shift occurred during the oxidation cycles. Nanosecond transient absorption spectral studies show that for the compounds containing strong electron donors (such as PTZ), either a short triplet state lifetime ( τ T = 0.47 µs for NPDI2 ) or no ISC was observed ( NPDI4 ). For the compounds with moderate or no electron donor attached in the molecular structure, long triplet state lifetimes were observed ( τ T = 86.9 µs for NPDI1 and τ T = 47.8 µs for NPDI3 ). For the compounds lacking ISC ability, an intermolecular triplet photosensitizing method, and long triplet state lifetimes were observed ( τ T = 46 µs for NPDI4 ).

Source: Chemistry - A European Journal

DOI: 10.1002/chem.71044

Authors: Mohd Wazid, Xi Chen, Peiwen Jiang, Jianzhang Zhao, Rajneesh Misra

Institutions: Indian Institute of Technology Indore, Dalian University of Technology, State Key Laboratory of Fine Chemicals

Language: English

Topic: Photochemistry and Electron Transfer Studies

Subfield: Physical and Theoretical Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funders: Council of Scientific and Industrial Research, India, Indian Institute of Technology Indore

Award: G1694608539