Nucleophilic Substitution By: Nucleophillic Substitution Introduction Nucleophilic substitution is a process in which a leaving group on a compound is replaced by a nucleophile. There are two different types of substitution reactions. They are known as SN1 and SN2 reactions. There are many differences between these two reactions. For example, SN1 are two step reactions, involving the formation of a carbocation intermediate, followed by a nucleophilic attack. These reactions are promoted by a polar protic solvent and are favored by […]
Absorption Spectrum of a Conjugated Dye By: Scott Holdren Abstract The absorption spectrum of a series of conjugated dyes is produced by a UV/VIS spectrometer to calculate the empirical parameter α and to find the length of the conjugated chain using the free electron model. Diluted solutions of each dye are analyzed using a UV/VIS spectrometer to determine the wavelength of maximum absorbance (λmax) for each dye. Using this wavelength, the best fit α is determined to be equal […]
Epoxidation of Geraniol: A Quest to Determine the Enantioselectivity of Two Epoxidation Procedures By: Ryan DeAngelis, Andre Mound Abstract The purpose of this experiment was to compare the enantioselectivity of the meta-chloroperoxybenzoic acid epoxidation procedure and the Sharpless Asymmetric Epoxidation. The enantioselectivity of each procedure in the epoxidation of geraniol was investigated via chiral shift 1H-NMR spectroscopy. The results indicated that the mCPBA epoxidation procedure did not exhibit enantioselectivity, whereas the Sharpless Asymmetric Epoxidation demonstrated enantioselectivity for the (2S, 3S)-epoxy […]
Competitive Nucleophiles By: Doug Kruse Abstract: The competitive nucleophilic reaction of two nucleophiles, chloride and bromide ion with tert-butyl alcohol have been studied in this experiment. Nucleophilic substitution at the tertiary carbon to form a haloalkane was observed. During nucleophilic substitution, a nucleophile replaces a leaving group from a carbon atom, using its lone pair electrons to form a new bond to the carbon atom.1 Nucleophilic substitution can occur through two pathways namely SN1 and SN2 reaction mechanism. The former […]
Thin Layer & Column Chromatography By: Lisa Mickey Introduction Thin layer chromatography (also known as TLC) is the physical separation of a mixture into its individual components by distributing the components between a stationary phase (the porous TLC plate) and a mobile phase (the solvent that moves through the stationary phase and carries the material that needs to be separated. The driving force to separate components is capillary action. This method can be […]
Distillation By: Tim Dimond Introduction/Purpose The purpose of this lab was to purify an unknown mixture of acetone/water by both fractional and simple distillation. This process is a viable method for separation of these two liquids because of the large separation in their boiling points. Material -Water and acetone mixture Equipment – A setup for fractional distillation and simple distillation -100 mL round bottom flask -Volume measuring equipment -Heating equipment Procedure Obtain 70 mL of the acetone/water solution in a […]
