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Updated: Jan 7, 2026

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Foto cromismo de merocianinas sustituidas con piridina a través de la formación reversible de enlaces C-N

He Li^1,2, Ya Liu^1,3, Feifan Sun¹

¹Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China.

Nature communications

|December 26, 2025

Abstract:

The reversible interconversion between spiropyran and merocyanine constitutes one of the most intensively investigated photochromic systems, enabling diverse applications in stimuli-responsive materials and optical imaging. Here, we report pyridine-substituted merocyanines (PMCs) as a class of photochromic molecules. Upon visible light irradiation, these compounds undergo an uncommon photoinduced C-N bond formation to yield spiroindolizine (SIZ) structures, accompanied by the color fading. The SIZs can thermally revert to the colored PMC form. This photochromism is marked by rapid response, high photo-switching ratio, robust water compatibility, and fatigue resistance. Furthermore, we have synthesized quinoline-substituted merocyanines and found that they can be bidirectionally switched by 660 nm and 500 nm light to form SIZ and PMC structures. Finally, we showed the photochromism of these molecules in solid matrices and demonstrated a light-controlled sequential switching function, highlighting their potential for advanced photonic applications.

Palabras clave:

merocianinas sustituidas con piridina fotocromismo formación de enlaces C-N espiroindolizina materiales fotónicos

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