In this experiment, sodium borohydride will be used to reduce 4-tert-butylcylohexanone into two 4-tert-butycycohexanol diastereoisomers with differing stereochemistry. Sodium borohydride is preferred over lithium aluminum hydride as a reducing reagent due to its “weak reducing agent” property. Using sodium borohydride allows for a more selective reduction around other functional groups, such as if you had a molecule that contains a carboxylic group and acetone, sodium borohydride will only reduce the ketone since it doesn’t have the capability of reducing the acid. The 4-ter-butylcyclohexanol diastereoisomers products were isolated by a liquid-liquid extraction involving dichloromethane in order to separate the organic and aqueous layer.
The purpose of this experiment is to establish the facial selectivity of the following reduction through analysis of the NMR usiing the identity and percent of each steroisomerstereoisomer present and calculating the ratios of the products. The reaction’s progress was tracked using TLC analysis and IR spectrum was taken to ensure the desired product is achieved.
During the experiment, when the addition of the sodium borohydride, the reducing agent, was added, the solution became a foggy white shade. When the 1.0mL of 0.05 HCl were
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This is due to the fact that the hydride more readily “attacks” from the axial direction, making the equatorial alcohol the major product, hence trans-4-tert-butylcyclohexanone. Sodium borohydride is not a sterically hindered reducing agent and can attack the 4-tert-butylcylohexanone from the top. Overall, this gives the more energetically stable
In an oxidation reaction, the number of C-H bonds decreases or the number of C-O bonds increases, while in a reduction reaction, the number of C-H bonds increases or the number of C-O bonds decreases. In the oxidation step of this reaction, 4-tert-butylcyclohexanone is formed from when a C-H bond is lost while a C-O bond is gained to create a carbonyl. In the reduction step, 4-tert-butylcyclohexanol is formed when the carbonyl is converted into an alcohol when a nucleophilic hydride attacks the carbonyl. Whether the OH is in the
Theory: One of the methods of preparing alkyl halides is via the nucleophilic substitution reactions of alcohols. Alcohols are inexpensive materials and easy to maintain. However, they are a poor leaving group the OH group is a problem in nucleophilic substitution, this problem is fixed by converting the alcohol into H2O.
group. The location of this hydroxyl functional group will impact the molecular structure of the
The Hydroxyl group on alcohols relates to their reactivity. This concept was explored by answering the question “Does each alcohol undergo halogenation and controlled oxidation?” . Using three isomers of butanol; the primary 1-butanol, the secondary 2-butanol and the tertiary 2-methyl-2-propanol, also referred to as T-butanol, two experiments were performed to test the capabilities of the alcohols. When mixed with hydrochloric acid in a glass test tube, the primary alcohol and secondary alcohols were expected to halogenate, however the secondary and tertiary ended up doing so. This may have been because of the orientation of the Hydroxyl group when butanol is in a different
The Purpose of this experiment is for the students to learn how to use sodium borohydride to reduce benzil to its secondary alcohol product via reduction reaction. This two-step reaction reduces aldehydes by hydrides to primary alcohols, and ketones to secondary alcohols. In order for the reaction to occur and to better control the stereochemistry and yield of the product, the metal hydride nucleophile of the reducing agents such as LiH, LiAlH4, or NaBH4 must be carefully chosen. Being that LiAlH4 and NaBH4 will not react with isolated carbon-carbon double bonds nor the double bonds from aromatic rings; the chosen compound can be reduce selectively when the nucleophile only react with
The synthesis of the alkyl halide n-Butyl Bromide from alcohol is the foundation for the experiment. During the isolation of the n-butyl bromide, the crude product is washed with sulfuric acid, water, and sodium bicarbonate to remove any remaining acid or n-butyl alcohol. The primary alkyl halide halide n-butyl bromide is prepared by allowing n-butyl alcohol to react with sodium bromide and sulfuric acid. The sodium bromide reacts with sulfuric acid to produce hydrobromic acid . Excess sulfuric acid acts to shift the equilibrium and speed up the reaction by producing a higher concentration of hydrobromic acid. The
3.0g of salicylic acid was weighed then 3.0mL of acetic anhydride and 6 drops of 85% H3PO4 were added to it. The mixture was warmed over a water bath for 5 minutes while stirring. After warming, 20 drops of distilled water was slowly added. 15mL of water was added then the solution was heated until it became clear. It was allowed to cool and was placed in an ice bath until the solution becomes cloudy. Using pre-weighed filter paper, the mixture was filtered and was allowed to dry in the filter paper.
We used TLC analysis to identify each product obtained from the dihydroxylation reactions by spotting a TLC plate with the product of our reaction, a solution of cis-cyclohexane, trans-cyclohexane, and a 50:50 mixture of the two. We then placed the plate in a beaker with ethyl acetate saturating the atmosphere to allow the TLC plate to develop. Finally, we compared Rf values of the components of the mobile phase, after the phase was completed. 100% ethyl acetate was used instead of 100% Hexane or a mixture of Ethyl Acetate, because ethyl acetate has high polarity and can separate the components of a mixture to elution, unlike hexane, which is non-polar, and therefore unable to separate the components of the mixture. A 50:50 mixture of both would not work, because the polar and non-polar compounds would neutralize the mixture, and thereby not separate the components of the mixture.
After 10 minutes the reaction liquid was separated from the solid using a vacuum filtration system and toluene. The product was stored and dried until week 2 of the experiment. The product was weighed to be 0.31 g. Percent yield was calculated to be 38.75%. IR spectra data was conducted for the two starting materials and of the product. Melting point determination was performed on the product and proton NMR spectrum was given. The IR spectrum revealed peaks at 1720 cm-1, which indicated the presence of a lactone group, and 1730 cm-1, representing a functional group of a carboxylic acid (C=O), and 3300cm-1, indicating the presence of an alcohol group (O-H). All three peaks correspond with the desired product. A second TLC using the same mobile and stationary phase as the first was performed and revealed Rf Values of 0.17 and 0.43for the product. The first value was unique to the product indicating that the Diels-Alder reaction was successful. The other Rf value of 0.43 matched that of maleic anhydride indicating some
Abstract: Using hypochlorous acid to convert secondary alcohol called cyclododecanol to the corresponding ketone which is cyclododecanone by oxidation.
Owing to its large acyl pocket, BChE is capable of accommodating larger substrates such as the four-carbon acyl-group of the BCh, making hydrolysis of BCh or the smaller ACh catalytically efficient (Radic et al., 1993). Furthermore, this principle explains why BChE was capable of effectively hydrolysing benzoylcholine which contains a large acyl group in the form of an aromatic ring (Figure1). When compared to AChE, whose acyl pocket is much smaller; BCh, suxamethonium (which contains a large acyl-quaternary nitrogen) and benzoylcholine are unable to effectively fit
In this experiment, the main objective was to synthesize a ketone from borneol via an oxidation reaction and secondly, to produce a secondary alcohol from camphor via a reduction reaction. Therefore, the hypothesis of this lab is that camphor will be produced in the oxidation reaction and isoborneol will be the product of the reduction reaction because of steric hindrance. For the oxidation step, a reflux will be done and then a microscale reflux for the reduction step. The products will be confirmed using Infrared spectroscopy, the chromic acid test, 2,4-DNP test and 13C NMR spectroscopy. The results of this
The products of interest within this experiment are 2-methyl-1-butene and 2-methyl-2-butene from sulfuric acid and phosphoric acid catalyzed dehydration of 2-methyl-2-butanol. The reaction mixture was then separated into its separate alkene components by steam distillation and then analyzed by gas chromatography (GC), Infrared Radiation (IR) spectroscopy, and Nuclear Magnetic Resonance (NMR) imaging. Gas chromatography is an analytical technique that is able to characterize if specific compounds exist in a reaction mixture, even if they are in low quantities, assess how much of a compound exists within a reaction mixture relative to other components within the sample, and determine the purity of an isolated product. In the case of this experiment, gas chromatography is used to analyze how pure the alkene reaction sample was and if any remnants of impurities or 2-methyl-2-butanol remained in the sample after isolation of alkene components.
The result was small white crystals, which were dry and had barely contained any moisture. The product was then dissolved in methylene chloride and dried with granular anhydrous sodium sulfate. The drying agent would have removed any water in the solution and presented a colorless solution. The solvent was evaporated and the product was collected; it had the appearance of small, white solids. Data Table 2 shows the results and calculations that were gathered after the completion of this experiment. A boiling point of the product was found to be 210℃. According to literature, the boiling of isoborneol should be 212℃. As a result, the product is most likely isoborneol. No errors had occurred during the course of the experiment, which is testified by the high yield of
4-boromo aniline failed in this reaction because of reduced solubility of its corresponding imines due to molecular weights increases. Although, in most cases, aldehyde derivatives did not constitute the product with acceptable yield, almost all the amines underwent smooth reactions to produce their derivatives in good to excellent yields at room