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What is the appropriate reaction conditions and stepwise procedure for the preparation of 2-chloro-4-nitroaniline from aniline and chlorine gas in the laboratory?

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The preparation of 2-chloro-4-nitroaniline from aniline and chlorine gas can be achieved through a two-step process: nitration followed by chlorination. Here's the stepwise procedure:Step 1: Nitration of aniline1. Dissolve 10 g of aniline in 50 mL of concentrated hydrochloric acid  HCl  to form anilinium chloride salt. This step is necessary because aniline is a strong base and will react with the nitration reagents if not protonated.2. Cool the anilinium chloride solution in an ice bath to maintain a low temperature  0-5C  during the nitration process.3. In a separate container, prepare a nitrating mixture by slowly adding 15 mL of concentrated nitric acid  HNO  to 15 mL of concentrated sulfuric acid  HSO  while stirring. Cool the mixture in an ice bath.4. Slowly add the nitrating mixture to the anilinium chloride solution, dropwise, while stirring and maintaining the temperature below 5C. This will form 4-nitroaniline.5. After the addition is complete, let the reaction mixture warm to room temperature and stir for an additional 30 minutes.6. Pour the reaction mixture onto crushed ice and filter the precipitate. Wash the precipitate with cold water to remove any remaining acid.7. Recrystallize the 4-nitroaniline from hot water or ethanol to obtain pure 4-nitroaniline.Step 2: Chlorination of 4-nitroaniline1. In a round-bottom flask, dissolve 10 g of 4-nitroaniline in 100 mL of glacial acetic acid.2. Cool the solution in an ice bath to maintain a low temperature  0-5C  during the chlorination process.3. Slowly bubble chlorine gas  Cl  through the solution while stirring and maintaining the temperature below 5C. The reaction will produce 2-chloro-4-nitroaniline.4. Continue bubbling chlorine gas until the reaction is complete. You can monitor the reaction progress by checking the color change of the solution  from yellow to orange-red  or by thin-layer chromatography  TLC .5. After the reaction is complete, pour the reaction mixture onto crushed ice and filter the precipitate. Wash the precipitate with cold water to remove any remaining acetic acid.6. Recrystallize the 2-chloro-4-nitroaniline from hot water or ethanol to obtain pure 2-chloro-4-nitroaniline.Note: Chlorine gas is highly toxic and corrosive. This reaction should be performed in a well-ventilated area or a fume hood, and appropriate personal protective equipment  gloves, goggles, lab coat  should be worn.
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