A mixture of aniline, glacial acetic acid, acetic anhydride and zinc dust is refluxed under anhydrous condition and then poured the mixture into ice cold water to get acetic anhydride precipitate. Its effectiveness in relieving pain was discovered soon thereafter, and it was used as an alternative to aspirin for many years in treating such common complaints as headache, menstrual cramps, and rheumatism. In this experiment, acetanilide was produced by acetylation of aniline with acetic anhydride. For the love of physics walter lewin may 16, 2011 duration. You have seen the mechanisms for all of the steps, although some of the reagents may be unfamiliar. The difference in their functional group leads to other subtle variations in physical and chemical properties between these two compounds. The preparation of acetanilide from aniline and acetic anhydride is a specific reaction that can be applied to the preparation of any amide from the corresponding amine and anhydride as shown by the following generic equation. Based on the above equation, complete the following equation for the preparation of phenacetin, a compound once used as an analgesic. If the reaction mixture has been kept excessively cold during the addition. Acetanilide is synthesized from aniline by acetylating it with acetic anhydride in presence of glacial acetic acid. To purify acetanilide by crystallization method using water. A simple laboratory report on the preparation of acetanilide in the laboratory. To prepare a sample of acetanilide from aniline chemistry lab manualncert solutions class 12 chemistry sample papers theory acetanilide is prepared by acetylating aniline with acetic anhydride in the presence of glacial acetic acid.
Acetanilide is prepared from aniline by acetylating it with acetic anhydride in the presence of glacial acetic. These metrics are regularly updated to reflect usage leading up to the last. Experiment 8 the preparation of acetanlide free download as word doc. To prepare and submit acetanilide from aniline labmonk.
Dissolve 2 g of aniline in 60 ml water and 2 ml conc. Article views are the countercompliant sum of full text article downloads since november 2008 both pdf and html across all institutions and individuals. To prepare acetanilide the replacement of one hydrogen atom of the nh2 group of aniline by ch3co group in the presence of glacial acetic. The synthesis of acetanilide comes about by the acylation of aniline with carboxylic acids. After all the hno 3, h 2 so 4 solution has been added, the reaction mixture is allowed to warm slowly to room temperature. Difference between aniline and acetanilide compare the. Apparatus round bottom flask 100 ml, water condenser, wiregauze, tripod stand, burner, ironstand. In this reaction, aniline acts as the nucleophile and acyl ch 3 co. This is the method used in the preparation of acetanilide from aniline.
Nitro anilines can be prepared by this type of reactions because nitration of aniline is not possible, amino group gets oxidised with nitrating mixture. Reaction mixture should first cooled and then poured in icecold water otherwise hydrolysis of acetanilide may take place. Preparation of acetanilide i take a 100 ml clean and dry r. Relative reactivies of anisole aniline and acetanilide. Aniline is toxic and can be absorbed through the skin. Acetanilide, synthetic organic compound introduced in therapy in 1886 as a feverreducing drug. Experiment 8 the preparation of acetanlide acetic acid. To this mixture taken in the flask, add 5 ml of aniline and fit a water condenser.
Bromination of acetanilide chemistry stack exchange. Preparation of acetanilide college of science chemistry department 1 preparation and purification of acetanilide purpose. Aniline is refluxed with glacial acetic acid in the presence of fused sodium acetate when acetanilide is obtained. In the presence of strong acids, oximes can undergo molecular rearrangement to. Preparation of dibenzal acetone materials required. If inhaled if breathed in, move person into fresh air. They are then able to compare the melting points of the impure and recrystallized acetanilide. Freshly distilled aniline should be used to get good results. Now, in the hood,prepare the bromine solution by adding 1. Separate the aniline from the aqueous mixture extract with ether remove the ether simple distillation or reduced pressure distillation vacuum distil the aniline. In an aqueous solution containing sodium bicarbonate, aniline reacts quickly with bromine to give 2,4,6tribromoaniline. A solution of sodium acetate will be added as a base to deprotonate the water soluble intermediate and to. Acetanilide is an odourless solid chemical of leaf or flakelike appearance.
Sulfanilamide is easily synthesized from aniline in four steps. Preparation of paminoazobenzene from aniline akzo n. Stirring with a glass rod may be necessary to help dissolve the acetanilide r. Nitration of aniline requires very strong conditions, however, and the yields mostly mnitroaniline are poor. The first step involves the addition of a protecting group to the amino substituent of aniline. Predicting the product of bromination of acetanilide. Presents the preparation of sulfanilamide from aniline, a synthesis that is shorter than the tradition method. The preparation used to be a traditional experiment in introductory organic. The crude acetanilide was dissolved in a solvent in a heating water bath. Show this safety data sheet to the doctor in attendance.
Aniline is slightly soluble in water and mixes readily with most organic solvents. These metrics are regularly updated to reflect usage leading up to the last few days. Preparation acetanilide aniline from aniline in the laboratory. Preparation of phenylamineaniline chemistry stack exchange. Concentrated hydrochloric acid can cause severe burns. Aniline is an aromatic amine with nh 2 group, and acetanilide is an aromatic amide with conh group. Aniline reacts with acetic anhydride to form acetanilide and the reaction is called acetylation. It is usually prepared by acetylation of aniline with acetic anhydride and glacial acetic acid.
Key difference aniline vs acetanilide aniline and acetanilide are two benzene derivatives with two different functional groups. It is also known as acetanilide, nphenylacetamide, acetanil, or acetanilid, and was formerly known by the trade name antifebrin. Learning activity 1 preparation of acetanilide abstract recrystallization is a common method of purifying organic substances through the difference in solubility at different temperature. Aniline is used to make a wide variety of products such as polyurethane foam, agricultural chemicals, synthetic dyes, antioxidants, stabilizers for the rubber industry, herbicides. Add 5 ml of distilled water to the test tube and then add 20 drops of acetic anhydride again using a medicine dropper fig. If you look at what you did, it is the same steps in a different order. It is not as basic as ammonia, since protonation destroys the interaction between the ring and the lone pair on the nitrogen atom, but even still, it is sufficiently basic pkb 9. Take 5 ml of acetic anhydride in a clean dry 100 ml conical flask and add 5 ml of glacial acetic acid and shake the contents thoroughly. Acetanilide is prepared from aniline when it reacts with acetic anhydrideglacial acetic acid in the presence of zinc dust. To prevent dinitration of the acetanilide, the nitrating mixture is added in small portions to the acetanilide solution and not vice versa so that the concentration of hno 3, is kept at a minimum.
First aid measures general advice consult a physician. Hcl 37% hcl by weight in water is added in order to dissolve the aniline in water. Aniline is a clear to slightly yellow liquid with a characteristic odor. Nacetylarylamine is an odourless solid chemical of leaf or flakelike appearance. The preparation used to be a traditional experiment in introductory organic chemistry lab classes, but it has now been widely replaced by the preparation of either paracetamol or aspirin, both of which teach the same practical. Nacetylarylamine has analgesic and feverreducing properties. Acetylation of aniline experiment chemistry libretexts. Thanks for a2a aniline when treated with acetoacetate will produce nacetyl aniline. Journal of chemical education, v56 n7 p488 jul 1979. You will be asked to calculate percent yield on every lab you do for the rest of. Why does aniline dissolve in hcl, where acetanilide does not. Acetic anhydride, an anhydride of acetic acid, acts here as a source of acyl group.
Bromination of acetanilide journal of chemical education. Preparation of acetanilide from aniline pharmadhunia. Preparation of acetanilide chemistry practicals class 12 byjus. Acetanilide can be produced by reacting acetic anhydride with aniline. This experiment has been used successfully with 2,000 students during. Aniline or phenylamine is a primary amine and basic in nature. Preparation of acetanilide from aniline amrita online lab. Chemistry stack exchange is a question and answer site for scientists, academics, teachers, and students in the field of chemistry. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. To synthesis acetanilide by reaction of aniline and acetic anhydride amine to amide. Preparationrecrystallization of acetanilide mendelset. Separate the aniline from the aqueous mixture extract with ether.
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