Iodination of salicylamide with nai bleach
Given that the cloud is so stable, aromatic compounds like benzene and its derivatives do not undergo electrophilic addition reactions as simple alkenes do.
Your Tasks: 1 Predict the product of the electrophilic iodination of salicylamide see Question 1 at the end of the lab2 synthesize and purify recrystallize the product, 3 collect an IR spectrum, interpret it, and determine if your prediction is correct see Question 5 at the end of the lab.
These latter effects are termed directing effects, and substituents are grouped according to whether they are ortho, para directors typically electron donators or meta directors typically electron withdrawers.
Using the information you collected on the compound that you synthesized, draw the structure of the product. The resulting product is classified as a substitution product since the electrophile substituted for a hydrogen on the ring.
Role of sodium thiosulfate in iodination
Take care to add the acid to the water. Given that your job in this lab is to determine where on the ring the iodine substitution occurs, you should find IR a very useful technique! Thus, we chose not to provide melting point data. Works very well. The solid will completely dissolve in 5 minutes or less. Calculate the theoretical and percent yield of iodinated salicylamide product assuming a monoiodination reaction. Show your calculations. In this experiment, you will be introduced to the use of the fingerprint region of the IR spectrum to determine the substitution pattern of aromatic rings. Use your knowledge of electrophilic aromatic substitution and the directing effects of substituents on an aromatic ring to answer the following questions. The strong peak at cm-1 indicates the 1,2-substitution pattern of salicylamide. The amide is a meta-director and the hydroxyl group is an ortho,para-director. What are the possible sites of iodination of the salicylamide ring? The experiment is an electrophilic iodination reaction of salicylamide, a popular analgesic, using environmentally friendly reagents--sodium iodide and household bleach.
This sufficiently dries the compound for use in collecting an IR spectrum. Thus, we chose not to provide melting point data. With no melting point for 3iodosalicylamide it is not in the literatureidentification of the product becomes fairly straightforward less critical analysis of data required.
Given that only the 4-iodo and 5-iodo isomers of salicylamide are known compounds, we chose not to use melting point for identification of the product. We instruct them to gently swirl the flask while warming it in their hands.
The solution will change colors from the initial clear reaction mixture to a dark red-brown to increasingly lighter shades of yellow. Related documents.
Iodination of salicylamide procedure
The IR spectrum of salicylamide, your starting material, is shown below. Place the salicylamide into a mL round-bottom flask. Show your calculations. E E H complex If the complex subsequently reacts with a nucleophilic species, the result would be an addition product, but a loss of aromaticity. While this is an important piece of information in organic structural determinations, IR can also provide a wealth of additional information about an organic compound. The strong peak at cm-1 indicates the 1,2-substitution pattern of salicylamide. Typically, this takes less than five minutes.
Todd Journal of Chemical Educationv85 n10 p Oct We developed an alternative electrophilic aromatic substitution reaction for the organic chemistry teaching laboratory.
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