Revisiting C4N4 Fluorophore: Theoretical Elucidation of the Origin of Fluorescent Properties of 2,5-Diaminopyrimidines and Strategic Applications to Pd Detection.

Miki Kohei, Itsuki Kondo, Go Kawamura, Yu Harabuchi, Satoshi Maeda, Naoya Kumagai

Abstract read

In one paragraph

Article in Chemistry (Weinheim an der Bergstrasse, Germany), 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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5 · Who and what money

Authors and funding

6 authors.

Miki KoheiGraduate School of Pharmaceutical Sciences, Keio University, Minato-ku, Tokyo, Japan.

Itsuki KondoGraduate school of chemical sciences and engineering, Hokkaido University, Sapporo, Hokkaido, Japan.

Go KawamuraGraduate School of Pharmaceutical Sciences, Keio University, Minato-ku, Tokyo, Japan.

Yu HarabuchiInstitute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, Hokkaido, Japan.

Satoshi MaedaInstitute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, Hokkaido, Japan.

Naoya KumagaiGraduate School of Pharmaceutical Sciences, Keio University, Minato-ku, Tokyo, Japan.ORCID https://orcid.org/0000-0003-1843-2592

Funding

Fusion Oriented REsearch for disruptive Science and Technology JPMJFR2221Japan Society for the Promotion of Science JP23H01952Japan Society for the Promotion of Science JP23H03808JST-FOREST JPMJFR2221KAKENHI 23H03809KAKENHI JP23H01952KAKENHI JP23H03808Mitsubishi Foundation and Mukai Science and Technology Foundation

6 · The paper itself

Abstract

Compact organic fluorophores are attractive scaffolds for probe design, yet their emission is often compromised by efficient nonradiative decay. Here, we introduce 2,5-diaminopyrimidine-based C4N4 as an intrinsically emissive, exceptionally small platform, which remains bright without extended π-conjugation. Systematic substitution at 4,6-positions with alkyl, alkenyl, and alkynyl groups reveals robust emission for alkyl and alkynyl derivatives, and a striking bimodality for alkenyls. TDDFT combined with ES/SC-AFIR mapped the S

Indexed as

artificial force induced reactionconical intersectionenergy shift methodfluorescent probeheavy metal detection

Identifiers

PMID41721553

DOI10.1002/chem.202503491

PMCPMC13174915

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.