The Role of Substituents in Optical Rotation of Oxiranes, Oxetanes, and Oxathietanes

Abstract

Taking as examples a series of oxiranes, oxetanes, and oxathietanes with different substituents, we study in a systematic way the role that the latter play on the optical rotation of the molecules. For this, we use time-dependent density functional theory together with a hierarchy of Dunning’s basis sets. The B3LYP and CAM-B3LYP exchange-correlation functionals are employed. We select results obtained with the CAM-B3LYP functional and the daug-cc-pVTZ basis set as our reference values. Additionally, specific rotation in all systems is calculated with the ORP basis set, specifically designed to carry out optical rotation calculations. The present study shows its good performance in CAM-B3LYP estimations of this property, providing results close to the reference values. The proper choice of the exchange-correlation functional proves to be much more important than that of the basis set. Considering the effect of the substituents, some of the presently investigated molecules show a behavior in line with earlier findings; however we have also found systems that do not match the conclusions previously available in the literature.

Systematic Analysis of the Role of Substituents in Oxiranes, Oxetanes, and Oxathietanes Chemical Shifts

“…In the present work, we investigate the proton chemical shifts in 12 model cyclic molecules, namely, oxirane, six oxetanes, two oxathietanes, cyclopropane, and two cyclobutanes, all containing different substituents from the following set: F, Cl, CN, and CCH. Geometrical parameters in the majority of the investigated systems are adopted from the work in ref . In the case of the four achiral molecules which were not studied in ref , i.e., molecule 12 containing, respectively, two fluoro, two chloro, two cyano, and two ethynyl substituents, the same methodology is employed to obtain the geometries, namely, the DFT method with the B3LYP functional and the 6-311++G** basis set .…”

“…Geometrical parameters in the majority of the investigated systems are adopted from the work in ref . In the case of the four achiral molecules which were not studied in ref , i.e., molecule 12 containing, respectively, two fluoro, two chloro, two cyano, and two ethynyl substituents, the same methodology is employed to obtain the geometries, namely, the DFT method with the B3LYP functional and the 6-311++G** basis set . Geometry optimization is followed by evaluation of the vibrational frequencies, confirming that all optimized structures correspond to real minima on the potential energy surface.…”

A Density Functional Theory Study of Optical Rotation in Some Aziridine and Oxirane Derivatives

“…[34,45,46] Jorge and co-workers [24,29,38] tested the AXZP basis sets in DFT calculations with the BP86, B3LYP, PBE0, M06, M06-2X and CAM-B3LYP functionals on different sets of three-, four-and higher membered rings and extrapolated to the basis set limit with an inverse cubic formula with the conclusion that quadruple zeta basis sets give results close to the basis set limit. Baranowska-Łaczkowska and coworkers [34,27,39] investigated both the performance of the LPol-n basis sets and of the especially for optical rotation optimized ORP basis set [34] at the DFT/B3LYP level, in the latter case for 31 small and medium-size molecules. They showed that the ORP and LPol-ds and LPol-dl basis sets give results comparable to much larger quadruple zeta basis sets.…”

“…Theoretical calculations of ORP have been made with many quantum chemical methods: [11–15] Hartree‐Fock (HF) calculations employing polarized, medium and large basis sets show reasonable accuracy, [16,17,18] while correlated post‐HF methods, i. e. density functional theory (DFT), [10,17–39] second order polarization propagator (SOPPA) [40] and coupled cluster (CC) [23,25–28,33,37,41–45] approaches, lead often to better agreement with experimental data. Nevertheless, the most employed approach is DFT with the B3LYP functional.…”

A Celebration of Women in Computational Chemistry

“…The results show that CAM-B3LYP estimations of optical rotation provide results close to the reference values. They conclude that the proper choice of the exchange-correlation functional proves to be much more important than that of the basis set . In another article, Nedyalkova and co-workers report DFT calculations (i.e., M062X, M11, and B3LYP) in combination with a continuum solvent model for the calculation of octanol/water (logKo/w) and octanol/air (logKo/a) partition coefficients.…”