Synthesis, Vibrational Spectra, and DFT Simulations of 3-bromo-2-methyl-5-(4-nitrophenyl)thiophene

A new thiophene derivative, 3-bromo-2-methyl-5-(4-nitrophenyl)thiophene (2), was synthesized through the Suzuki coupling reaction of 4-bromo-5-methylthiophen-2-ylboronic acid (1) and 4-iodonitrobenzene, and its structure was confirmed by nuclear magnetic resonance (NMR), low and high resolution mass spectrometry (HRMS), Fourier transform infrared spectroscopy (FT-IR), and X-ray investigations of the crystal structure. The FT-IR spectra (4000–400 cm–1), Raman spectra (4000–100 cm–1), and theoretical vibrational frequencies of this new substance were investigated. Its theoretically established geometric parameters and calculated vibrational frequencies are in good agreement with the reported experimental data. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies and other related parameters of the compound were calculated. The ionization potentials given by the B3LYP and HF (Hartree–Fock) methods for this new compound are –0.30456 and –0.30501 eV, respectively. © 2017, Springer Science+Business Media, LLC, part of Springer Nature.