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So, we did Green Chemistry Electrophilic Aromatic Nitration of Tyrosine

Experiment. My starting material was 0.5g and my experiment yield was 0.3575g. Pls calculate the percentage yield. Experiment 28 from my textbook that we didn't perform is Nitration of Methyl Benzoate.  Pls, help me with the attachement below. Thanks for all your help so far William!!! The three IR is for you to compare them. Thanks once again! If you need more information, pls let me know. 

List of Chemicals and Hazards L-Tyosine, Concentrated Nitric Acid, Concentrated Sulfuric Acid, Ethyl Acetate Hazards: Nitric and Sulfuric acids are both extremely corrosive. Take extreme caution. Addition of the mixture can be highly exothermic. This mixture reacts violently with acetone so be sure glassware is cleaned thoroughly and dry. Experimental Procedure Synthesis: Weigh 0.5 grams of L-tlrosine into a 10 mL round bottom flask and suspend in about 2 mL of deionized water. Attach a Claisen adapter to the top of the round bottom flask. In a conical vial, 0.36 mL of concentrated HzSOa and0.47 mL of concentrated HNO: should be carefully mixed while cooling in an ice bath. The cooled acid mixture is added dropwise through the Claisen head with gentle stirring of the tyrosine suspension. Cooling in an ice-water bath should be maintained through the reaction in order to avoid potential dinitration products. The reaction should be cooied sufficiently and the rate of addition kept slow enough to prevent reflux. After addition, let the reaction continue in the ice-bath for about 15 minutes. The reaction is then allowed to warm to room temperature before placing in a water bath at 40"C for 30 minutes. Isolation: The reaction mixture is then cooled in an icebath until crystallization occurs. The soiution is filtered using a Buchner funnel and the crude product is collected. Recrystallization can be done to purify the crystals. The crystals are washed with about 1 mL of ethl'l acetate and then recrystallized in roughly 5 mL of water. Waste: The acidic aqueous waste can be neutralized and sent down the drain. Ethyl acetate needs to be collected and disposed of in the nonhalogenated waste. Solid products can also go in the nonhalogenated waste. Results The melting point of the final product is 234"C. Impure samples may decompose before that temperature. IR of the crystalline product should also be obtained. Record your mass of your final product and calculate the percentage yield of your experiment. Extra Information For those looking for some extra information on green chemistry, your lab text has an excellent essay on the topic starting on page 268.It covers many of the topics that are presented in the prelab materials while also looking at how atom economy plays an important role in the development of chemical syntheses.
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Green Chemistry Electrophilic Aromatic Nitration of Tyrosine Adapted from "A Green Starting Material for Electrophilic Aromatic Substitution for the Undergraduate Organic Laboratory" T. Michelle Jones-Wilson, Journal of Chemical Education, Vo132, No. 4, April2005 What is Green Chemistry? In our modern world, we have become increasingly aware of our impact on the world and environment around us. In chemistry, this is no different. Chemists must be aware of the sources of their starting rnaterials and the amount of waste that is generated in synthetic processes. Feedstocks for organic chemistry reactions many times come from nonrenewable resources such as crude oil. Reactions have also been done in organic soivents which must be disposed of carefully which generates a massive amount of waste. Green chemistry aims to change this by looking for renewable sources for starting materials, atom economy during chemical processes, and limiting waste byproducts. Many of the goals of green chemistry can be summarized in the principle of green chemistry seen below. Applications for the Organic Laboratory So, why discuss this in an educational setting? While industrial scale processes generate far more waste, academic chemical laboratories produce their fair share. Think about the amount of waste that you collect that must be disposed of during a 3-hour lab session. Some of this waste is limited by doing microscale procedures, but large amounts of waste are still generated. Not only is can this waste be environmentally problematic, but the cost of disposing of waste can eat up budget of a chemistry department. For these and other reasons, making students aware of green chemistry principles is a highly important topic Electrophilic Aromatic Substitution Electrophilic Aromatic Substitution is one of the more important chemical reactions that we study during Organic II. It allows us to add functional groups to the normally unreactive benzene ring. Problematically for the educational laboratory, ffiffiy of the starting materials for EAS tend to be quite toxic and from nonrenewable sources. Our goai for this experiment is to complete an electrophilic substitution reaction with a nontoxic, renewable starting material. We will be attempting this reaction by using tyrosine, an amino acid. o _? ll H3N:C&OH CH, t- a\ v I OH
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