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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
High resolution millimeter-wave spectroscopy of cyclopropylphosphine-borane
Roman A Motiyenko1, Laurent Margulès, Jean-Claude Guillemin
1Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523, Université de Lille 1, F-59655 Villeneuve d'Ascq, France. motienko@univ-lille1.fr
The Journal of Physical Chemistry. A
|January 14, 2012
Summary
We studied the microwave spectrum of cyclopropylphosphine-borane, revealing its most stable antiperiplanar form. The internal rotation barrier of the borane group was determined using spectral analysis and ab initio calculations.
Area of Science:
- Physical Chemistry
- Spectroscopy
- Computational Chemistry
Background:
- Cyclopropylphosphine-borane (C(3)H(5)PH(2)-BH(3)) is a molecule with potential applications in various chemical processes.
- Understanding its conformational preferences and internal dynamics is crucial for predicting its reactivity and properties.
Purpose of the Study:
- To investigate the microwave spectrum of cyclopropylphosphine-borane.
- To determine the stable conformations and internal rotation barriers of the molecule.
- To validate experimental findings with high-level ab initio calculations.
Main Methods:
- Microwave spectroscopy in the 150-195 GHz frequency range.
- High-level ab initio quantum chemical calculations.
- Analysis of rotational spectra in excited vibrational states.
Main Results:
- The antiperiplanar (ap) conformer was identified as the most stable form.
- A synclinal conformer was predicted to be higher in energy by 7.3 kJ/mol.
- The barrier to internal rotation of the BH(3) group was determined to be 9.616(15) kJ/mol.
Conclusions:
- The study successfully assigned the microwave spectrum of cyclopropylphosphine-borane.
- Experimental results align well with theoretical predictions from quantum chemical calculations.
- The determined internal rotation barrier provides valuable insights into the molecule's dynamics.
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