Differentiation and identification of 5F-PB-22 and its isomers

Several countries have reported numerous detections of quinolin-8-yl 1-(5-fluoropentyl)-1H-indole-3-carboxylate (5F-PB-22) and for some countries, their legislation does not control all the positional isomers. This study was to separate and identify the fluoro positional isomers in the pentyl chain of fluoro-PB-22 using gas chromatography–mass spectrometry (GC–MS), solid deposition gas chromatography–infrared detection (GC–IRD) spectroscopy and Nuclear Magnetic Resonance (NMR) spectroscopy. These findings which were then used to identify the positional isomer of fluoro-PB-22 present in seized sample is presented. [Display omitted] •Differentiation of 5F-PB-22 and its three other positional isomers in the pentyl chain.•Analytical data of all fluoro positional isomers were reported.•Possibility of misidentification if only GC–MS was used without drug reference standards.•Solid deposition GC–IRD and NMR spectroscopies were used as the identification techniques. Quinolin-8-yl 1-(5-fluoropentyl)-1H-indole-3-carboxylate (5-Fluoro-PB-22 or 5F-PB-22; QUPIC N-(5-fluoropentyl) analog), is a synthetic cannabinoid which mimics the effects of cannabis. Several countries have reported numerous detections of this compound and its abuse has led to adverse effects including death. The aim of this study was to separate and identify the fluoropentyl positional isomers of fluoro-PB-22 using gas chromatography–mass spectrometry, solid deposition gas chromatography–infrared detection spectroscopy and 1H and 13C nuclear magnetic resonance spectroscopy. Data acquired from these multiple techniques can assist forensic laboratories lacking the reference drug standard(s) to identify the specific isomer of fluoro-PB-22 in seized material.