Objective The objective of this experiment is to produce a sample of hexaphenylbenzene from the Diels-Alder addition of tetraphenylcyclopentadienone and diphenylacetylene, both of which were synthesized from previous lab procedures. Procedure Part A- Preparation of Hexaphenylbenzene • In a 25 mL round-bottom flask, 0.50 g (0.0013 mol) of tetraphenylcyclopentadienone and 0.50 g (0.0028 mol) of diphenylacetylene were poured, and with a heating mantle and a ring stand, the flask was vigorously heated. This heating was performed for a continuous 20 minutes in order to allow the reaction to occur thoroughly, which required a large amount of energy, and the melting solids were stirred from time to time with a spatula. It was observed that the solids melted into a purple liquid, which at around 10-12 minutes, turned into a distinct brown color. After the allotted time, 10 mL …show more content…
Afterwards, the mixture was allowed to cool to room temperature, at which point an additional 15 mL of “hexanes” were added, and the flask was placed in an ice bath. After allowing the flask to cool to room temperature, a layer of light brown crystals was observed at the bottom of the flask. These crystals were collected with a vacuum filtration setup (which was created from a Buchner funnel and Buchner flask, which was attached with a hose to a vacuum), and were further washed with about 10-15 mL of diphenyl ether. After collecting, washing, and allowing the crystals to dry, a yield of 0.25 g of a whitish powder was recorded, presumably hexaphenylbenzene. The product was disposed of, as this
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In cycle one, the double displacement reaction, Cu(s) + 4HNO3(aq) → Cu(NO3)2(aq) + 2NO2(g) + 2H2O(l) occurred, the result of the reaction was that the reaction mixture began to bubble with the copper filling dissolving and a vapor like substance leaving the reaction. Furthermore, when water was added, the color change, from brown to a blue color pigment. Then in Cycle two, another double displacement reaction occurred, Cu(NO3)2(aq) + 2NaOH(aq) → Cu(OH)2(s) + 2NaNO3(aq), which resulted in the reaction becoming cloudy and a darker shade of blue. Following cycle two, a decomposition reaction occurred as the result of heat being administered to the mixture, thus the following reaction occurred in cycle three, Cu(OH)2(s) → CuO(s) + H2O(l). As a
The goal of the experiment is to synthesize a bromohexane compound from 1-hexene and HBr(aq) under reflux conditions and use the silver nitrate and sodium iodide tests to determine if the product is a primary or secondary hydrocarbon. The heterogeneous reaction mixture contains 1-hexene, 48% HBr(aq), and tetrabutylammonium bromide and was heated to under reflux conditions. Heating under reflux means that the reaction mixture is heated at its boiling point so that the reaction can proceed at a faster rate. The attached reflux condenser allows volatile substances to return to the reaction flask so that no material is lost. Since alkenes are immiscible with concentrated HBr, tetrabutylammonium bromide is used as a phase-transfer catalyst.
Observations The purpose of this experiment was to be able to synthesize triphenylmethyl bromide from triphenylmethanol by a trityl carbocation intermediate. During the experiment, 0.100 g of triphenylmethanol was placed into a small test tube. The triphenylmethanol looked like a white powder. Next 2 mL of acetic acid was added to the test tube and the solution turned a cloudy white color.
Chem 51LB Report Ngoc Tran - Student ID # 72048507 The purpose of this lab is to examine the composition of three components of gas products of elimination reaction under acidic condition by conducting the dehydration of primary and secondary alcohol, and under basic condition by conducting the base-induced dehydrobromination of 1-bromobutane and 2-bromobutane. Then gas chromatography is used to analyze the composition of the product mixtures. Gas chromatography (mobile phase) is used to analyze the composition of three components of the gas products. A syringe needle with gas product is injected into the machine, and the component is eluted and the composition is related to the column or the peaks.
METHOD: The following procedure was taken from the 2017 Millsaps College lab manual.1 The experiment was split into two parts, part A and part B. Part A was to find the heat capacity while part B determined the specific heat of an unknown metal. This was the final goal of the lab. To start, a temperature probe had to be connected to a LabQuest2 data collection device. 100.0 mL of deionized had to be added into a Styrofoam cup.
The objective of this two-part experiment was to in Part I, create 4-tert-butylcyclohexanone via oxidation of 4-tert-butylcyclohexanol to provide a source of ketone for reduction procedures. Part II of the experiment was conducted preforming a series of reduction reactions in effort to asses the diastereoselectivity of aluminum isopropoxide (MPV reduction), sodium borohydride (NaBH4), and L-selectride when reacted with 4-tert-butylcyclohexanone. The methods used for analysis were TLC, IR, and 1HNMR spectroscopy. An oxidation of 4-tert-butylcyclohexanol was conducted to produce the ketone, 4-tert-butylcyclohexanone using oxidizing reagent, sodium hypochlorite in glacial acetic acid solvent.
A white solid was formed as a product with 59.3% yield. In this reaction tetraphenylcyclopentadienone used as the diene, which was condensed with a highly reactive alkyne dienophile (diphenylacetylene). Heat was used to overcome the diene’s enhanced activation energy. The mixture turned dark brown indicated the loss of carbon monoxide, which made this reaction, overall, irreversible. The result was formation of a high yield hexaphenylbenzene which is more stable than the first product, The Reason is that the delocalized electrons in the rings give more stability to hexaphenylbenzene as compared to the dimethyl
Abstract: The purpose of this experiment was identifying two compounds in an unknown mixture via liquid-liquid extraction and acid-base reactions. The compounds in the unknown mixture isolated by using recrystallization, and then their identity was determined by comparing the experimental melting point values with actual melting points. Unknown mixture 5 contained a carboxylic acid, 4-methylbanzoic acid, and a non-ionizable organic compound, 1,2-diphenylethane-1,2-dione.
The product is transferred from the ring of the Hickman still into a pre-weighed vial for analysis. The percent yield of the recovered product is calculated, and IR spectroscopy and gas chromatography are used to analyze the purity and percent composition of different alkene products. Chemical Reactions: References: Crago, Kathleen. et. al,.
The wax melted first, followed by the salt, and lastly the sugar. The salt not only burned before the sugar, but developed a brown color throughout most of the substance at a faster pace. In the water solubility test, the salt dissolved in the water, as soon as it was properly mixed and the sugar dissolved in the water as well, but was stirred for a longer period of time until it was completely dissolved. The wax did not dissolve in the water, however bits of the substance broke off from the main piece. With this information, the final results included: wax as a nonpolar covalent compound, since the substance melted first and was not soluble in water; salt as a polar covalent compound, since the substance was soluble in water and the second to melt; and sugar as an ionic compound because the substance melted last and was soluble in
Melting point data was used to confirm the identity of the product as diphenylacetylene. The expected melting point of diphenylacetylene is 59-61℃, according to its MSDS sheet. While there was a discrepancy in this temperature range and the melting point range observed, the melting point was significantly lower than that of meso-stilbene dibromide, which is 241℃. The data hence confirms the formation of diphenylacetylene. The error could have been caused due to impurities in the diphenylacetylene crystals, such as leftover ethanol, or triethylene glycol, which would destabilize the lattice structure of the crystal, making it melt at a lower temperature than expected.
The product obtained was (2S, 3R)-2, 3-dibromo-3-phenylpropanoic acid and (2R, 3S)-2, 3-dibromo-3-phenylpropanoic acid, which are enantiomers. This was determined through melting point analysis. The melting point range for the product was 198 to 202 degrees Celsius, which is a lot close to the given melting point of the anti-addition product, 202-204 degrees Celsius. The given melting point range was 93.5-95 degrees Celsius. Furthermore, the syn-addition product is unlikely and difficult to produce due to stereochemistry selectivity.
The solution is pale yellow in color, and from this it is assumed that the bromine is in excess and the cholesterol is the limiting reagent. The cholesterol dibromide solution is placed in an ice bath, the reason behind this is that the colder the environment is, the less soluble the solution becomes, therefore, the cholesterol dibromide begins to crystallize. In this experiment, it took a while for the cholesterol dibromide to fully crystallize, so acetic acid was added as a precipitant. A wash solution is prepared which consisted of acetic acid and methyl tert-butyl ether to rinse the flask for the solid cholesterol dibromide that was stuck to the flask. Cholesterol dibromide was isolated by using the vacuum filtration technique.
The next part of the experiment, alkyl halide classification tests, will be used to determine the degree of substitution of the alkyl halide that was formed during the reaction. For this experiment specifically, this allows for the verification of the formation of a primary bromoalkane from the primary alcohol. The success of the experiment will be determined by a percent yield, analysis of the infrared spectroscopy reading, and the results of the alkyl
In 1927 Diesbach and Von der Weild of Fribourg University, carried out a reflex reaction using ortho-dibromobenzene with cyanide and obtained a blue coloured compound with 23% yield. In 1928 at the Grangemouth plant of Scottish Dyes Ltd a blue-green impurity has formed inside the reaction vessel during the