Synthesis, characterization, crystal structure, and DFT study of 3,4-Diphenyl -1<i>H</i>-pyrrolo[2,3-b]pyridine

3,4-Diphenyl-1<i>H</i>-pyrrolo[2,3-b]pyridine, a useful organic building block, was obtained via a four-step reaction and the structure was determined using FT-IR, ¹H NMR, ¹³C NMR, and mass spectrometry, and the single crystals were characterized using X-ray diffraction analysis. The optimal molecular structure, <b>1-2</b> (49.95%), was calculated using density functional theory, and was consistent with the structure determined based on single-crystal diffraction; the relative Gibbs free energy of conformer <b>1-2</b> was 0.001255 kcal mol⁻¹. In addition, the molecular electrostatic potentials and frontier molecular orbitals of the title compound were investigated, and surface analysis was performed to further reveal its physicochemical properties.