Synthesis, spectral analysis, and theoretical investigations of diphenyl fumarate

Abstract

Diphenyl fumarate is synthesized from maleic anhydride and phenol under solvent-free conditions. The structure of the product is characterized by FTIR, 1H NMR, and 13C NMR. The molecular structure is optimized using the density functional theory approach at the B3LYP/6-311G(d,p) level and the structural parameters are analyzed. Theoretical vibrational frequencies are investigated at the same level; the 1H NMR and 13C NMR are simulated using the default gauge-independent atomic orbital method at the B3LYP/6-31G(d) level and the solvation model density implicit continuum solvation model for chloroform; chemical shifts are scaled using scaling factors available on the cheshirenmr.info website (accessed 12 September 2021). In addition, the UV-Vis absorption and fluorescence emission are simulated using the time-dependent method at the PBE38/6-311G(d,p) level. All the calculated spectral values are compared with the experimental data. A generally good agreement between the experimental and theoretical results is found. The results reveal diphenyl fumarate as a candidate substrate for small-molecule organic fluorophores with a large Stokes shift. This work provides a detailed experimental and theoretical study on the structural and spectral properties of diphenyl fumarate, and thus provides proof for the novel applications of diphenyl fumarate and its derivatives.