2026-04-27T21:42:13Zhttps://uvadoc.uva.es/oai/request

oai:uvadoc.uva.es:10324/462322025-09-04T11:48:21Zcom_10324_1186com_10324_931com_10324_894col_10324_1404

Structure Determination, Conformational Flexibility, Internal Dynamics, and Chiral Analysis of Pulegone and Its Complex with Water Krin, Anna Pérez Cuadrado, Cristobal Pinacho Morante, Pablo Quesada Moreno, María Mar López González, Juan Jesús Avilés Moreno, Juan Ramón Blanco Rodríguez, Susana López Alonso, Juan Carlos Schnell, Melanie Quimica Espectroscopía de rotación In the current work we present a detailed analysis of the chiral molecule pulegone, which is a constituent of essential oils, using broadband rotational spectroscopy. Two conformers are observed under the cold conditions of a molecular jet. We report an accurate experimentally determined structure for the lowest energy conformer. For both conformers, a characteristic splitting pattern is observed in the spectrum, resulting from the internal rotation of the two non-equivalent methyl groups situated in the isopropylidene side chain. The determined energy barriers are 1.961911(46) kJmol-1 and 6.3617(12) kJmol-1 for one conformer, and 1.96094(74) kJmol-1 and 6.705(44) kJmol-1 for the other one. Moreover, a cluster of the lowest energy conformer with one water molecule is reported. The water molecule locks one of the methyl groups by means of a hydrogen bond and some secondary interactions, so that we only observe internal rotation splittings from the other methyl group with an internal rotation barrier of 2.01013(38) kJmol-1. Additionally, the chirality-sensitive microwave three-wave mixing technique is applied for the differentiation between the enantiomers, which can become of further use for the analysis of essential oils. 2021-04-16T17:27:15Z 2021-04-16T17:27:15Z 2021-04-16T17:27:15Z 2018 info:eu-repo/semantics/article Chemistry: A European Journal, 2018, vol. 24, p. 721-729 0947-6539 http://uvadoc.uva.es/handle/10324/46232 10.1002/chem.201704644 721 3 729 Chemistry - A European Journal 24 spa https://chemistry-europe.onlinelibrary.wiley.com/doi/full/10.1002/chem.201704644 info:eu-repo/semantics/openAccess Wiley-V C H Verlag Gmbh Wiley-V C H Verlag Gmbh