Fig. 2. (a) 1H-NMR spectrum of racemic molecule 1 in CDCl3 with and without 1 equivalent of R-VAPOL-PA showing only alpha proton and methyl proton respectively (b) 1H-NMR stack plot of R and R/S molecule 1 with 1 equivalent of R-VAPOL-PA along with the chemical structure in the schematic shows the chemical shift difference in ppm (ΔδR/S) observed at the respective proton sites. (c) Effect of concentration of CSA (R-VAPOL-PA) on the chemical shift difference of molecule 1 in the solvent CDCl3. (d) 1H-NMR spectrum of R/S molecule 1 showing discriminate aromatic protons with R-VAPOL-PA as CSA. All the spectra were recorded at 500 MHz magnetic field. The black circles indicate the peaks corresponding to both isomers.
