Induced chirality in a binary complex of trifluoroacetic acid with camphor
摘要
Reported here are the infrared absorption and infrared vibrational circular dichroism (VCD) spectra of a binary complex of trifluoroacetic acid (TFAA) with two enantiomers of camphor in carbon tetrachloride (CCl4) solution. The spectral analysis reveals formation of two distinct isomeric complexes in the liquid at room temperature. The measured VCD spectra of the binary complex shows distinct transitions with respect to selected vibrational modes of the TFAA moiety. The observations have been corroborated by the predictions of density functional theory (DFT) calculations. The results demonstrate the occurrence of chirality induction in an achiral counterpart in the non-covalent complex of a chiral molecule.
Graphical abstractSynopsis. The graphical abstract illustrates that due to the formation of a hydrogen-bonded binary complex between trifluoroacetic acid and the two enantiomers of camphor, chirality is induced in the otherwise achiral trifluoroacetic acid molecule. This induced chirality is evidenced by both experimental and theoretical vibrational circular dichroism spectra of the complex.