Bromination is a type of electrophilic aromatic substitution reaction where one hydrogen atom of benzene or benzene derivative is replaced by bromine due to an electrophilic attack on the benzene ring. The purpose of this experiment is to undergo bromination reaction of acetanilide and aniline to form 4-bromoacetanilide and 2,4,6-tribromoaniline respectively. Since -NHCOCH3 of acetanilide and -NH2 of aniline are electron donating groups, they are ortho/para directors due to resonance stabilized structure. Even though the electron donating groups activate the benzene ring, their reactivities are different and result in the formation of different products during bromination. In acetanilide, the lone pair of the nitrogen is delocalized into the …show more content…
Then percent yield was calculated to be 67.57%. The isolation of less product resulted from using less amount of acetanilide than 0.07g at the beginning of the experiment. In addition, the melting point of the product was measured to be 164.8-168.50c, which is in the range of the normal melting point of 4-bromoacentailide, 165-1690c. This confirmed the formation of 4-bromoacetanilide from the bromination of acetanilide. From the bromination of 0.05g aniline, 0.156g of the product was collected. The percent yield was calculated to be 88.1%. Some amount of the product was lost when transferring the product from the Buchner funnel to the balance to measure its mass. To ensure the formation of the desired product, melting point of the product was measured to be 119.8-121.90c, which is in the range of the normal melting point of 2,4,6-tribromoanilne, 120-1220c. Thus, the product was indeed …show more content…
In this experiment, it was possible to produce the major products from bromination of acetanilide and aniline. 0.075g of 4-bromoacetanilide and 0.156g of 2,4,6-tribromoanilne were collected from bromination of 0.07g acetanilide and 0.05g aniline with the percent yield of 67.57% and 88.1% respectively. At the end of the experiment, to prove the formation of the major products, melting point of the products were measured. The melting point of the product from the bromination of acetanilide was 164.8-168.50c, which is in the range of the melting point of 4-bromoacetanilide, 165-1690c, as reported on the Chemical Book, CAS Database List (chemicalbook.com). The melting point of the product from the bromination of aniline was 119.8-121.90c, which is in the range of the melting point of 2,4,6-tribromoaniline, 120-1220c, as indicated on PubChem, Open Chemistry Database (pubchem.ncbi.nlm.nih.gov). This verified the formation of the major products. Overall, one can say that the experiment was
After 28 minutes, the mixture stopped boiling, and approximately 4.5 ml of bromobenzene was added drop by drop in the mixture, and color of the mixture was turned light brown orange. Then, the phenylmagnesium bromide was cooled in ice bath for a few minutes, and 10 ml of anhydrous diethyl ether was added in the mixture by using the syringe. After that, approximately 2.3 ml of methyl benzoate was added to the reaction, and it was added slowly slowly because the reaction was exothermic which needed to be cool in order to maintain a gentle reflux. Once all the methyl benzoate solution was added, the heating mantle was removed from the reaction flask and was cooled to the room temperature. During the reaction, a milky white salt began to precipitate, and the reaction flask was swirled for ten minutes until most of the reaction became visibly subdivided.
The last goal was to determine the percent yield of a product formed during a reaction with the unknown compound. Experimental Design The first day of lab consisted of various preliminary tests that helped identify the unknown compound.
The better the leaving group, the faster the reaction making Br a better leaving group than Cl. Tertiary-butyl iodide reacts faster than tertiary-butyl bromide via S_N 2 mechanism because iodide is a better leaving group than bromide. True or False? True. 1-Chlorobutane (2.5 mL, d=0.886) in 20 mL of acetone is reacted with 90 mL of a 15 wt% solution of NaI in acetone.
In this test, primary halides precipitate the fastest while secondary halides need to be heated in order for a reaction to occur. Comparison of the rates of precipitation of the obtained product to standard 1° and 2° bromide solutions will show whether the product is a primary or secondary
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.
The following lab period the solid was weighed (0.0483 g) and percent yield was calculated (65.5%) with the limiting reagent being tetraphenylcyclopentadienone. The melting point was determined. The first melting point was 204-204.9 °C and the second melting point was 215.6-215.9°C. Finally, an infrared spectroscopy was obtained for the
Chem 51 LB Experiment 3 Report Scaffold: Bromination of Trans-Cinnamic Acid 1. The goal of this experiment was to perform a halogenation reaction through the addition of two bromides from pyridinium tribromide. This was accomplished by reacting trans-cinnamic acid with pyridinium tribromide. After the reaction took place, melting point analysis was conducted to find out the stereochemistry of the product, which could either be syn-addition, anti-addition, or syn + anti-addition. 2.
The purpose of this experiment is to perform a two step reductive amination using o-vanillin with p-toluidine to synthesize an imine derivative. In this experiment, 0.386 g of o-vanillin and 0.276 g of p-toluidine were mixed into an Erlenmeyer flask. The o-vanillin turned from a green powder to orange layer as it mixed with p-toludine, which was originally a white solid. Ethanol was added as a solvent for this reaction. Sodium borohydride was added in slow portion as the reducing agent, dissolving the precipitate into a yellowish lime solution.
The first experiment involved in this four-week project was the extraction and
Nevertheless, the latter is not used in this experiment since it is very reactive and extremely flammable. On the contrary, NaBH4 is relatively mild and it can be used with protic solvents. In this manner, 1.507 grs of the ketone 9-fluorenone were mixed with 30.0 ml of 95% ethanol in a 125 ml Erlenmeyer flask. The bright yellow mixture was stirred during 7 minutes until all the components were dissolved.
The objective of this experiment was to use an aldol condensation reaction to synthesize 3-nitrochalcone from 3- nitrobenzaldehyde. This was accomplished with a Diels-Alder reaction that utilized 3-nitrobenzaldehyde, acetophenone, ethanol, and sodium hydroxide. The mechanism for the synthesis of 3-nitrochalcone is presented in Figures 1 and 2. The alpha carbon on the acetophenone is deprotonated. This is followed by the attack of the alpha carbon anion on the carbonyl carbon on the 3-nitrobenzaldehyde.
In this experiment rate of reaction with different reactants concentration: KI (0.010 M), KBrO3 (0.040 M), and HCl (0.10 M) will be observed. So, this is reaction between iodide and bromate ion under acidic conditions: 6 I- (aq) +BrO3-(aq)+ H+(aq)→ 3I2(aq) + Br-(aq)+ 3H2O The end of the reaction, will be determined by observing color change of solution. Thus, solution should shange color to blue.
Results 8. The obtained product was 4-tert-butylbenzyl phenol ether. This leads the unknown compound # 51 to be tert-butyl phenol. 9. Theoretical yield =
The literature melting point range of methyl trans-cinnamate is ~34-38oC (Aldrich).4 The obtained melting point of the crude was 34.5-35.5oC, which is a highly narrow range of less than 1oC difference and it also falls within the expected melting point range. Hence, the crystal lattice structure of the product is largely intact, requiring an even amount of thermal energy to melt the sample. The experimental melting point range indicates the crude product is relatively pure with minimal impurities. The percent yield was satisfactory, having a 68% yield. To optimize this yield, consider the steps in how the reagents are introduced to the reaction mixture in terms.
The percent yield was 22.33%. In most cases, that means that a lot of possible product was lost. However, in this case, that was not true. When Benzaldehyde reacted with the Wittig reagent, it produced two products: E-Stilbene and Z-Stilbene. The Z product was a liquid, while the E product was a solid.