Synthesis of fluorescent [1,2,4]triazolo[1,5-a]pyrimidines and study of their photophysical behavior
- 1Bioorganic Compounds Research Group, Department of Chemistry, Universidad de Los Andes Carrera 1 No. 18A-10 Bogotá 111711 Colombia +57 1 3394949. Ext. 2080
- 2Departamento de Química, Universidad de Nariño Pasto AA 520002 Colombia
Abstract
The synthesis and photophysics of a family of [1,2,4]triazolo[1,5-a]pyrimidines bearing strategically tuned substituents are reported. Products were obtained in 58–94% yield by reacting 5-amino-1,2,4-triazoles with β-enaminones under solvent-free microwave conditions; notably, precursor heteroamines were obtained in 79–82% yield via a simple and novel protocol. Substituent-dependent solvatofluorochromism showed that dyes with a dimethylamino group exhibited exceptional optical behavior, including hydrochromism and acidochromism in acetonitrile (ϕF = 98% in THF at ∼450 nm; turn-off fluorescence to 10% in water and with TFA; LOD of 9.0–12.6 µM), due to intramolecular charge transfer (ICT) within the 7-arylated heterocyclic core; this process is altered by a methyl substituent on the triazole moiety. DFT and TD-DFT calculations were used to correlate the spectroscopic properties of eight of the synthesized products.
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BibTeX
@article{cruz2026synthesis,
title = {{Synthesis of fluorescent [1,2,4]triazolo[1,5-a]pyrimidines and study of their photophysical behavior}},
author = {Silvia Cruz and Alexander Ladino-Bejarano and Cristian Rivera-Moyano and Jaime Portilla},
journal = {RSC advances},
year = {2026},
month = nov,
doi = {10.1039/d6ra08535k},
url = {https://europepmc.org/article/PMC/PMC13729017},
note = {CC BY},
}
RIS
TY - JOUR
TI - Synthesis of fluorescent [1,2,4]triazolo[1,5-a]pyrimidines and study of their photophysical behavior
AU - Silvia Cruz
AU - Alexander Ladino-Bejarano
AU - Cristian Rivera-Moyano
AU - Jaime Portilla
PY - 2026
DA - 2026/11/03
JO - RSC advances
DO - 10.1039/d6ra08535k
UR - https://europepmc.org/article/PMC/PMC13729017
AB - The synthesis and photophysics of a family of [1,2,4]triazolo[1,5-a]pyrimidines bearing strategically tuned substituents are reported. Products were obtained in 58–94% yield by reacting 5-amino-1,2,4-triazoles with β-enaminones under solvent-free microwave conditions; notably, precursor heteroamines were obtained in 79–82% yield via a simple and novel protocol. Substituent-dependent solvatofluorochromism showed that dyes with a dimethylamino group exhibited exceptional optical behavior, including hydrochromism and acidochromism in acetonitrile (ϕF = 98% in THF at ∼450 nm; turn-off fluorescence to 10% in water and with TFA; LOD of 9.0–12.6 µM), due to intramolecular charge transfer (ICT) within the 7-arylated heterocyclic core; this process is altered by a methyl substituent on the triazole moiety. DFT and TD-DFT calculations were used to correlate the spectroscopic properties of eight of the synthesized products.
SN - 2046-2069
ER -