Ab initio study of chiral recognition in the propylene imine·hydrogen peroxide complex

Abstract

High level ab initio calculations were employed to study the chiral recognition effect in several chiral molecular pairs that consist of the propylene imine and hydrogen peroxide molecules. The potential energy surfaces for the complexes formed between S-cis-1,2-propylene imine and the two enantiomeric forms of hydrogen peroxide were constructed, using the calculated interaction energies at different separations and orientations. The energy calculations were done using the MOLPRO suite of programs with CCSD(T)/cc-pVDZ. The energies were counterpoise corrected at every point to eliminate the basis set superposition error. Complete geometry optimizations were further carried out for the molecular complexes consisting of the cis- or trans-propylene imine isomers and the two enantiomeric forms of hydrogen peroxide. The geometry optimizations were done using the Gaussian 98 and 03 suites of programs, with MP2/aug-cc-pVDZ being the highest level used. Altogether, eight stable complexes were identified, and the corresponding dissociation energies were calculated with MP2/aug-cc-pVTZ. The largest chirodiastaltic energy is found at 0.74 kcal mol(-1) for the (syn)trans-propylene imine.hydrogen peroxide complexes, where hydrogen peroxide acts as a hydrogen donor and is on the opposite side of the ring from the methyl group. The rotational constants, dipole moments, and harmonic frequencies of the complexes are presented to assist future spectroscopic investigations.

Chirality Recognition in the Glycidol⋅⋅⋅Propylene Oxide Complex: A Rotational Spectroscopic Study

“…[16] Second-order Møller-Plesset perturbation theory (MP2) [17] with the 6-311 [18] was chosen because of its proven performance for the H-bonded chiral contact pairs. [19,20] Eight possible rotameric conformations for the Gly monomer were confirmed to be true minima and the two most stable conformers identified as gÀG + and g + GÀ are the only ones with an appreciable population at room temperature. The gÀG + conformer was predicted to be approximately 2.5 kJ mol À1 more stable than g + GÀ.…”

Chiral discrimination in hydrogen‐bonded complexes of butan‐2‐ol (m‐form) and hydrogen peroxide

“…The trend of four energies of "ag" and "gg" [D e , D o , D e (corr), and D o (corr)] are similar to that of "ga." In general, the D o dissociation energies seem to provide the best match with the experimental observations [9]. This may be due to the fact that BSSE tends to overcorrect with the relatively small basis set, which is still far from completion [6,16]. Therefore, we decided to use the D o dissociation energies to further discuss the differences in binding energies among the systems studied.…”

“…Leutwyler and coworkers did detailed theoretical analysis on the molecular complex of HOOH with oxirane (Ox) and its derivatives in chiral discrimination [1]. This has inspired subsequent ab initio studies of chiral discrimination for other chiral molecules, such as the ROOH dimer (RAH and CH 3 ) [2], (HOOH)n, n from 2 to 10 monomers [3], HOOR dimer (RAH, CH 3 , CF 3, and HCO) [4], PO⅐⅐⅐PO [5], PI⅐⅐⅐HOOH [6], HOOH⅐⅐⅐ CH 3 OOH [7], Butan-2-ol (h-form)⅐⅐⅐HOOH [8] and a set of model systems with zero (Ox⅐⅐⅐EtOH), one (PO⅐⅐⅐EtOH), and two (DMO⅐⅐⅐EtOH) methyl functional groups at the hydrogen bond acceptor oxirane [9], etc.…”

Chiral discrimination in hydrogen-bonded complexes of 2-fluorooxirane with hydrogen peroxide

“…Research on chiral discrimination has received significant attention in recent years. Many papers [4][5][6][7] have been published concerning chiral discrimination. Recent reviews [8À10] provide a comprehensive discussion on experimental investigations and theoretical studies of chiral discrimination.…”