A Microwave Spectroscopic Investigation of the Networked Structure of 3-Hydroxytetrahydrofuran-H₂O

Abstract

The rotational spectra of nine isotopomers of the 3-hydroxytetrahydrofuran-water complex were recorded using a Fourier transform microwave spectrometer. The spectra are assigned to the networked structure of the complex, with intermolecular hydrogen bonds from the hydroxyl to the water oxygen and from water to the furanose-ring oxygen. Ab initio calculations, at the MP2/6-31G** level, indicate that this is the lowest energy structure of the complex, and it is based on the lowest-energy ring-puckering conformation of the 3-hydroxytetrahydrofuran monomer, C 4′ -endo. Stark effect measurements were used to determine the projections of the dipole moment on the principal inertial axes: µ a ) 1.2 (3) D, µ b ) 1.8 (2) D, µ c ) 0.7 (4) D, and µ tot ) 2.2 (2) D.

Direct Spectroscopic Detection of the Orientation of Free OH Groups in Methyl Lactate–(Water)1,2 Clusters: Hydration of a Chiral Hydroxy Ester

“…[10] studies of only a handful of chiral molecule-water clusters, such as alaninamide-water, [11] 3-hydroxytetrahydrofuran-water, [12] glycidol-water, [13] and propylene oxide-(water) 1,2 [14] have been reported. Herein, we report rotational spectroscopic and high-level ab initio computational studies of methyl lactate (ML)-(water) 1,2 clusters.…”

“…Detailed knowledge about the chiral molecule-water interactions at the molecular level is crucial to achieve a comprehensive understanding of the observed phenomena.Unlike the condensed-phase measurements, jet-cooled high-resolution spectroscopy can differentiate conformations of isolated chiral-molecule-water clusters with subtly different structures and provide accurate structural and relative stability information about them. Although jet-cooled highresolution spectroscopy has been successfully used to study small (organic) molecule-water adducts, such as nitric acidwater, [7] formamide-(water) 1,2 , [8] glycine-(water) 1,2 , [9] and trifluoroacetic acid-(water) 1,2,3 , [10] studies of only a handful of chiral molecule-water clusters, such as alaninamide-water, [11] 3-hydroxytetrahydrofuran-water, [12] glycidol-water, [13] and propylene oxide-(water) 1,2 [14] have been reported. Herein, we report rotational spectroscopic and high-level ab initio computational studies of methyl lactate (ML)-(water) 1,2 clusters.…”

Photo‐ionization spectroscopy and mass spectrometry of some molecular and supramolecular asymmetric systems in the isolated state

“…Like many other five-membered ring molecules, the (R)-and (S)-enantiomers of 3-hydroxytetrahydrofuran (Th R and Th S ) may present several ring-puckered conformations. 17,18 Among these, the C 4 endo structure is found to be the global minimum on the MP2/ 6-31G* potential energy surface, while C 2 endo structure is only 1.34 kcal mol À1 less stable. 17,18 This stability difference is in substantial agreement with that calculated at the QST2-MP2-6-31G* level of theory.…”

“…17,18 Among these, the C 4 endo structure is found to be the global minimum on the MP2/ 6-31G* potential energy surface, while C 2 endo structure is only 1.34 kcal mol À1 less stable. 17,18 This stability difference is in substantial agreement with that calculated at the QST2-MP2-6-31G* level of theory. 19 The photoelectron valence spectra of the Th R/S enantiomers are characterized by two bands, shifted by ca.…”

Direkter spektroskopischer Nachweis spezifischer Orientierungen freier OH‐Gruppen in Methyllactat‐(Wasser)1,2‐Clustern: Hydratation eines chiralen Hydroxyesters

“…B. Salpetersäure-Wasser, [7] Formamid-(Wasser) 1,2 , [8] Glycin-(Wasser) 1,2 [9] und Trifluoressigsäure-(Wasser) 1,2,3 , [10] allerdings wurde nur über einige wenige Wassercluster von chiralen Molekülen berichtet, wie Alaninamid-Wasser, [11] 3-Hydroxytetrahydrofuran-Wasser, [12] Glycidol-Wasser [13] und Propylenoxid-(Wasser) 1,2 . Hochauflçsende spektroskopische Methoden wurden zwar erfolgreich auf Untersuchungen von Addukten kleiner (organischer) Moleküle mit Wasser angewendet, z.…”