Perturbing the O-H^…O Hydrogen Bond in 1-oxo-3-hydroxy-2-propene

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Chemical Physics

Background:

• The study investigates the interactions between 1-oxo-3-hydroxy-2-propene and various Lewis acids.
• Understanding these interactions is crucial for predicting chemical reactivity and stability.

Purpose of the Study:

• To identify and characterize equilibrium and transition structures on the potential energy surfaces of 1-oxo-3-hydroxy-2-propene with Lewis acids.
• To determine the binding energies and interconversion barriers between different structural isomers.
• To compute charge-transfer energies and nuclear spin-spin coupling constants.

Main Methods:

• *Ab initio* MP2/aug'-cc-pVTZ calculations were employed.
• Potential energy surfaces were mapped to identify stable and transition structures.
• EOM-CCSD (Equation of Motion Coupled Cluster Singles Doubles) method was used for computing spin-spin coupling constants.

Main Results:

• Two distinct equilibrium structures were identified: one with Lewis acid interaction at the C=O group and another at the O-H group.
• Structures with C=O group interaction exhibit greater binding energies.
• Low barriers for interconversion from O-H to C=O bound structures suggest only C=O bound isomers are experimentally observable at low temperatures.
• Spin-spin coupling constants show a second-order dependence on interatomic distances with high correlation.

Conclusions:

• The study elucidates the preferred binding sites and energetic stability of Lewis acid complexes with 1-oxo-3-hydroxy-2-propene.
• Computational predictions provide insights into experimental observability of different isomers.
• The calculated spin-spin coupling constants offer a basis for experimental verification and further theoretical studies.