- 4-Ethylbenzophenone was synthesized utilizing the Friedel-Crafts acylation from the precursors of ethylbenzene and benzoyl chloride, catalyzed by aluminum chloride. Characterization was achieved via refractometry, GC-MS, IR and HNMR. Refractometry yielded a refractive index of 1.5932 ± 0.0001, notably higher than literature value indicating the presence of impurities. GC-MS detected the presence of all three isomers of ethylbezophenone, including the ortho form (2%), the meta form (7%) and the para form (78%). GC-MS also revealed the presence of diethylbenzophenone impurities which totaled 13% of the product. IR spectroscopy identified characteristic phenol stretching around 3030 cm⁻¹ and alkyl stretching around 2900 cm⁻¹ and ketone C=O stretching at 1655 cm⁻¹ . HNMR experienced instrumentation difficulties however sufficient data was collected to identify characteristic ethyl triplet and quartet peaks at 1.3 and 2.7 ppm, respectively. Although the product was not pure, utilizing the data gained via GC-MS the yield was determined to be 60% of the targeted 4-ethylbenzophenone.