A combination of proton spin diffusion NMR and molecular simulations to probe supramolecular assemblies of organic molecules in nanoporous materials

[EN] In this work we show the use of high-resolution H MAS NMR to distinguish between two kinds of aggregation states of (1R,2S)-ephedrine, a chiral organic structure directing agent, occluded within AFI-type microporous aluminophosphates. We investigate in particular the supramolecular assembly of...

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Detalles Bibliográficos
Autores: Dib, Eddy, Bernardo-Maestro, Beatriz, López Arbeloa, Fernando, Pérez-Pariente, Joaquín, Gómez-Hortigüela Sainz, Luis
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/304472
Acceso en línea:http://hdl.handle.net/10261/304472
Access Level:acceso abierto
Descripción
Sumario:[EN] In this work we show the use of high-resolution H MAS NMR to distinguish between two kinds of aggregation states of (1R,2S)-ephedrine, a chiral organic structure directing agent, occluded within AFI-type microporous aluminophosphates. We investigate in particular the supramolecular assembly of the molecules through π⋯π type interactions of their aromatic rings when confined within the one-dimensional AFI channels. A series of high-resolution two-dimensional spin diffusion spectra combined with molecular simulations and DFT calculations allowed us to distinguish different aggregation states of ephedrine molecules and precisely estimate the distances between the aromatic rings and their closest protons inside the zeolite channels as a consequence of distinct proton spin diffusion profiles.