2024-03-29T05:55:38Zhttps://uvadoc.uva.es/oai/requestoai:uvadoc.uva.es:10324/489982022-07-18T09:32:59Zcom_10324_1186com_10324_931com_10324_894col_10324_1404
2021-10-11T09:30:24Z
urn:hdl:10324/48998
How aromatic fluorination exchanges the interaction role of pyridine with carbonyl compounds: The formaldehyde adduct
López Alonso, Juan Carlos
Macario Farto, Alberto
Maris, Assimo
Alkorta, Ibon
Blanco Rodríguez, Susana
Producción Científica
The rotational spectrum of the weakly bound complex
pentafluoropyridineꞏꞏꞏformaldehyde has been investigated using
Fourier transform microwave spectroscopy. From the analysis of the
rotational parameters of the parent species and of the 13C and 15N
isotopologues, the structural arrangement of the adduct has been
unambiguously established. The full ring fluorination of pyridine has a
dramatic effect on its binding properties: It alters the electron density
distribution at the π-cloud of pyridine creating a π-hole and changing
its electron donor-acceptor capabilities. In the complex, formaldehyde
lies above the aromatic ring with one of the oxygen lone pairs, as
conventionally envisaged, pointing toward its centre. This lone
pairꞏꞏꞏπ-hole interaction, reinforced by a weak C-HꞏꞏꞏN interaction,
indicates an exchange of the electron-acceptor roles of both
molecules when compared to the pyridineꞏꞏꞏformaldehyde adduct.
Tunnelling doublets due to the internal rotation of formaldehyde have
also been observed and analysed leading to a discussion on the
competition between lone pairꞏꞏꞏπ-hole and π ꞏꞏꞏπ staking interactions.
2021-10-11T09:30:24Z
2021-10-11T09:30:24Z
2021
info:eu-repo/semantics/article
Chemistry – A European Journal, 2021, vol. 27, n. 55, p.13870 –13878
0947-6539
https://uvadoc.uva.es/handle/10324/48998
10.1002/chem.202102163
13870
55
13878
Chemistry – A European Journal
27
1521-3765
eng
https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.202102163
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
© 2021 The Authors
Attribution-NonCommercial-NoDerivatives 4.0 Internacional
Wiley