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Updated: Nov 8, 2025

Light-driven Molecular Motors on Surfaces for Single Molecular Imaging
Published on: March 13, 2019
Pairing multicomponent stators with aromatic rotators for new emissive molecular rotors
Ma Carmen García-González1, Jorge Espinosa-Rocha1, Lizbeth A Rodríguez-Cortés1
1Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior S.N., Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico. lmiranda@unam.mx brodriguez@iquimica.unam.mx.
Abstract:
We demonstrate here that the Ugi-Sonogashira protocol can be successfully used to obtain five new molecular rotors 10a-e with strong emission. They have been synthesized by combining multicomponent Ugi stators and several aromatic rotary components: phenylene, p-xylene, naphthalene and anthracene. The synthesized conjugated rotors are highly fluorescent (Φf = 0.39 to Φf = 0.10), and changes in their emission were observed upon variations of the surrounding media. Particularly, we found that they are sensitive to aggregation (THF/water) or high viscosity (methanol/glycerol) conditions. This work paves the way to develop new emissive rotors with exciting photophysical properties.
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