Synthesis, spectral characterization, crystal and molecular structure studies of 5-(5‑bromo‑2-thienyl)-1-(phenyl)-3-phenyl-2-pyrazoline

Abstract

The title compound 5-(5‑bromo‑2-thienyl)-1-(phenyl)-3-phenyl-2-pyrazoline has been synthesized and the structure was characterized using 1H NMR, 13C NMR, IR techniques and finally the structure was confirmed by X-ray diffraction studies. The IR spectrum of 5-(5‑bromo‑2-thienyl)-1-(phenyl)-3-phenyl-2-pyrazoline showed that absorptions in at 3064 cm−1 for C-H sp2, 2907 cm−1 for C-H sp3, 1561 and 1591 for C = C aromatic bond stretchings. The 1H and 13C NMR spectra of revealed the existence of all protons and carbons for the structure. The X-ray crystal structure studies revealed that pyrazoline ring in the structure is in an envelope conformation. The structure possesses a chiral centre at C5 with R conformation. The thiophene ring in the structure is affected by π conjugation.