A comparative VCD study of methyl mandelate in methanol, dimethyl sulfoxide, and chloroform: explicit and implicit solvation models.

摘要: Vibrational absorption (VA) and vibrational circular dichroism (VCD) spectra of methyl mandelate, a prototype chiral molecule, in series organic solvents, namely methanol (MeOH-d4), dimethyl sulfoxide (DMSO-d6), chloroform (CDCl3), have been measured the finger print region from 1800 to 1150 cm−1. Implicit solvation models form polarizable continuum model explicit employed independently simultaneously. The goal is evaluate their efficiencies dealing with solvent effects each solution establish general strategy adequately account for solvents. Molecular dynamics (MD) simulation radial distribution function analysis performed aid construction models. Initial geometry searches carried out at B3LYP/6-31G(d) level mandelate monomer its 1 : 1 1 : 2 solute–solvent hydrogen-bonded complexes. B3LYP/cc-pVTZ has used all final optimizations, frequency, VA VCD intensity, optical rotation dispersion (ORD) calculations. results show that inclusion explicitly implicitly same time significant impacts on appearance spectra, crucial reliable spectral assignments when solvents are capable hydrogen-bonding interactions solutes. When no strong solvent–solute case expected, gas phase adequate interpretation, while implicit improves frequency agreement experiment. ORD aforementioned different concentrations under 5 excitation wavelengths also measured. comparison between calculated experimental supports conclusions drawn investigations.