2 research outputs found
Hydride Dissociation Energies of Six-Membered Heterocyclic Organic Hydrides Predicted by ONIOM-G4Method
Hydride dissociation energy is of great importance in
understanding
the hydride-donating abilities of organic hydrides. Although the hydride
dissociation energies of some organic hydrides have been experimentally
measured, much less attention has been focused on the investigation
of these quantities from the first principles of physics. Herein,
we developed an ONIOM-G4 method and carefully benchmarked this new
method against 48 experimental hydride dissociation energies of diverse
bulky molecules. It was found that with the combined methods of the
HF/6-31+G(d,p)//IEFPCM/Bondi1.15 solvation model, the ONIOM-G4 method
can predict the hydride dissociation energies with an error bar of
only 1.7 kcal/mol. With the newly developed ONIOM-G4 method, we then
systematically studied the hydride dissociation energies of six categories
of biologically and pharmaceutically important six-membered heterocyclic
organic hydrides, namely, the organic hydrides containing 1,4-dihydropyridine,
1,4-dihydropyrazine, 1,4-oxazine, 1,4-thiazine, 4H-pyran, and 4H-thiopyran
ring structures. An extensive hydride dissociation energy scale containing
over 100 six-memebered heterocyclic organic hydrides has been established,
which may find applications in both synthetic organic chemistry and
mechanistic studies of various chemical or biological processes involving
transferring of the hydride anion