An experiment on the synthesis of camphor from isoberneol
Overall theoretical yield: 0. Sublimation is not a very accurate method as recrystalization or chromatography. The experimental IR showed a weak O-H stretch at The O-H stretch may be due to the presence of water in the sample, rather than the alcohol in isoborneol, and the C-H stretches in the experimental and literature IR spectra of both isoborneol and isobornyl acetate are interchangeable save for variations in strength. Draw out the step by step mechanism of the reduction of camphor with sodium borohydride showing the expected stereochemistry of the products. After the acetic acid is added, 5 ml of bleach NaOCl is added to the mixture and then placed underneath the previously erected apparatus. C compared to the literature value at deg. The reduction mechanism is often shown with a hydride H- ion attacking the carbonyl carbon.
Camphor is known to sublimate from solid to vapour at high temperature. You have seen this reagent before, as that employed for the synthesis of a-chloro alcohols from alkenes the chlorine analog of the reaction of alkenes with bromine in water.
A consequence of this is a very slow reaction.
Biochem J. IR spectrum for the synthesized camphor product shown at the top. While the basic principles and operations are the same as those in the macroscale experiments that have been used so far in the course, the techniques and equipment employed for sample manipulation, reactions, extractions, distillation, recrystallization, etc.
Synthesis of camphor lab report
Oxidation of isoborneol is an exothermic reaction, in order to avoid the creation of side product;the temperature should be controlled below 40 degrees Celsius. For isoborneol, the results were not as clear. Carefully add 12 mL of iced water. Excess HOCl that remains after can be destroyed by sodium bisulfite reducing agent. Add and mix a spatula-tip full or 5 drops of the test compound, followed by 1 mL of 2,4-DNP reagent. References 1. Sublimation is a phase change in which a solid phase passes directly into thevapor without going through an intermediate liquid phase. However, there exists chromium compounds that are known to be corrosive and generally harmful and pose as a legal disposal issue due to their harmful nature. The process of replacing a double-bonded oxygen atom with a hydrogen atom and hydroxide ion is a type of reaction known as reduction. However, there exists chromium compoundsthat are known to be corrosive and generally harmful and pose as a legal disposal issue due to theirharmful nature. Why might one assign a partial negative charge to the hydrogens in sodium borohydride? This is the active oxidizing agent. Errors in measuring reactants and reagents, transfers between containers, and inadequate conditions to allow the reaction to fully consume all the reactants could have all contributed to these poor yields in all three steps. Also, compare the different results when they are added to A water; B ethyl acetate; C methanol. Sublimation is not a very accurate method as recrystalization or chromatography.
In this experiment camphor will be prepared by oxidizing a secondary alcohol, isoborneol. The camphor yield was particularly striking, and was likely due to two mishaps: loss of camphor product during an aborted attempt at vacuum filtration and multiple rounds of liquid-liquid extraction involving imprecise draining.
Excess HOCl that remains after can be destroyed bysodium bisulfite reducing agent.
Synthesis of camphor pdf
Low yields, especially for camphor, were likely due to spills, multiple liquid-liquid extractions, errors in measurement, and incomplete reactions. Neither of these ought to be present in camphor, and were not present in the literature IR as shown by SDBS or the lab standard obtained by Bard. Absorptions at During the reduction of camphor, the reducing agent can approach the carbonyl face from either the exo side the re face near the one carbon bridge to form borneol, or from the the endo side the si face with the two cabon bridge to form isoborneol. Both reagents are ready sources of hydride ion H:- , a very strong base and when associated with aluminum or boron, a good nucleophile. Allow the vacuum to pull for about 10 minutes to dry the solid. A mixture of borneol and isoborneol gave the following 1HNMR signals with the given integrations 2. Reference IR spectrum of - -camphor purchased from Sigma Aldrich. Excess HOCl that remains after can be destroyed bysodium bisulfite reducing agent. There was, once again, significant melting point depression. How might the geometry of the product change OH in an endo or exo position?
One of the simplest methods of preparation uses sodium borohydride NaBH4 as a reducing agent. Conclusion The purpose of this experiment was to synthesize camphor in a multistep synthesis beginning with camphene.
The O-H stretch may be due to the presence of water in the sample, rather than the alcohol in isoborneol, and the C-H stretches in the experimental and literature IR spectra of both isoborneol and isobornyl acetate are interchangeable save for variations in strength.
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