Williamson ether experiments are commonly performed by students in undergraduate organic chemistry instructional laboratory courses. In this multioutcome experiment, students were provided 4-bromophenol and one of three alkyl halides: 1-bromopentane, 1-bromobutane, or 1-bromo-3-methylbutane. The alkyl halides served as the unknown component of the experiment, and students were given these three as unknown candidates. After isolating the product from the reaction mixture, students analyzed their products using FT-IR and benchtop 1H NMR spectroscopies. The experimental results herein summarize the inclusion of this experiment in the large enrollment second-semester organic chemistry laboratory course over four semesters.

Ortho-benzyne has been well studied by both experiment and theory. Its substituted variants, however, have been less carefully examined. Benchmark data are computed for unsubstituted ortho-benzyne using several density functional theory functionals and basis sets, up to cc-pVQZ. Optimized geometries for the substituted ortho-benzyne as well as harmonic vibrational frequencies and singlet–triplet splittings are computed using the benchmarked functionals. A proximal (syn)­OH substitution causes a mean θ1 distortion of +8.1 ± 1.4° from ortho-benzyne. Substituting in the proximal position with F shifts the singlet–triplet splitting by +4.5 ± 0.4 kcal mol–1 from ortho-benzyne. Natural bond orbital analysis, including natural Coulomb electrostatics, elucidates the presence of three influences from the selected substituents: hyperconjugative, resonance, and electrostatic effects.

Listeria monocytogenes (L. monocytogenes) are a common foodborne pathogen responsible for many foodborne illness outbreaks in recent years. Currently, Listeria contamination in food products is identified only through molecular tests conducted in diagnostic laboratories. No established phage-based diagnostic methods for L. monocytogenes during food production or processing are used. Here we report a potentially disruptive rapid diagnostic method based on electrochemical biosensing principles that use bacteriophages as bioreceptors for selective identification and quantification of L. monocytogenes. Electrochemical biosensors are good alternatives to molecular detection methods due to their ease of use, high specificity, sensitivity, and low cost. Bacteriophages can serve as excellent biorecognition elements in biosensors due to their robust stability in a range of environmental conditions and their ability to distinguish between live and dead bacterial cells. The impedimetric biosensing platform for L. monocytogenes detection was developed by immobilizing P100 bacteriophage onto quarternized polyethylenimine modified carbon nanotubes using an in-house developed molecular tethering method. The resulting sensor showed high selectivity and sensitivity toward L. monocytogenes with a limit of detection of 8.4 CFU/mL. Initial results demonstrate that the biosensing platform is highly reliable in its selectivity towards its target analyte, L. monocytogenes.