Solvent-Dependent Self-Association of Chiral 2-Acetoxy-2-Phenylacetic Acid Revealed by Infrared and Vibrational Circular Dichroism Spectroscopy
- 1School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India, 700032
Abstract
The solvent-dependent self-association of chiral 2-acetoxy-2-phenylacetic acid (APA) was investigated in CCl4, CDCl3, and DMSO-d6 solvents, using infrared (IR) and Vibrational Circular Dichroism (VCD) spectroscopy, supported by density functional theory calculations. Concentration-dependent IR measurements revealed progressive formation of self-associated species in CCl4 and CDCl3, whereas no significant concentration dependence was observed in DMSO-d6. Band-fitting analysis and comparison of experimental and calculated IR and VCD spectra indicate that hydrogen-bonded APA dimers with an antiarrangement of the phenyl rings are the dominant self-associated species in CCl4 and CDCl3. In contrast, the high polarity of DMSO-d6 suppresses self-association and favors a doubly hydrogen-bonded 1:1 APA–DMSO-d6 complex involving O-H…O and C-H…O interactions. The results demonstrate that solvent polarity strongly controls the balance between solutesolute and solute-solvent hydrogen bonding and highlight the sensitivity of VCD spectroscopy to molecular association and intermolecular interactions in solution.
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BibTeX
@misc{datta2026solventdependent,
title = {{Solvent-Dependent Self-Association of Chiral 2-Acetoxy-2-Phenylacetic Acid Revealed by Infrared and Vibrational Circular Dichroism Spectroscopy}},
author = {Anwesha Datta and Tapas Chakraborty},
howpublished = {ChemRxiv},
year = {2026},
month = sep,
doi = {10.26434/chemrxiv.15008344/v1},
url = {https://chemrxiv.org/doi/full/10.26434/chemrxiv.15008344/v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - Solvent-Dependent Self-Association of Chiral 2-Acetoxy-2-Phenylacetic Acid Revealed by Infrared and Vibrational Circular Dichroism Spectroscopy
AU - Anwesha Datta
AU - Tapas Chakraborty
PY - 2026
DA - 2026/09/04
PB - ChemRxiv
DO - 10.26434/chemrxiv.15008344/v1
UR - https://chemrxiv.org/doi/full/10.26434/chemrxiv.15008344/v1
AB - The solvent-dependent self-association of chiral 2-acetoxy-2-phenylacetic acid (APA) was investigated in CCl4, CDCl3, and DMSO-d6 solvents, using infrared (IR) and Vibrational Circular Dichroism (VCD) spectroscopy, supported by density functional theory calculations. Concentration-dependent IR measurements revealed progressive formation of self-associated species in CCl4 and CDCl3, whereas no significant concentration dependence was observed in DMSO-d6. Band-fitting analysis and comparison of experimental and calculated IR and VCD spectra indicate that hydrogen-bonded APA dimers with an antiarrangement of the phenyl rings are the dominant self-associated species in CCl4 and CDCl3. In contrast, the high polarity of DMSO-d6 suppresses self-association and favors a doubly hydrogen-bonded 1:1 APA–DMSO-d6 complex involving O-H…O and C-H…O interactions. The results demonstrate that solvent polarity strongly controls the balance between solutesolute and solute-solvent hydrogen bonding and highlight the sensitivity of VCD spectroscopy to molecular association and intermolecular interactions in solution.
ER -