Purpose:You will carry out the multi-step synthesis of the epoch-making antibacterial drug, sulfanilamide. Reactions and Physical Properties:Procedure:Day 1 (3/19): Carry out everything in the hood! To a dry dram vial with a stir bar, add dichloromethane (0.5 mL) and aniline (2.50 mmol). Immediately cap the vial with a rubber septum. Place this vial in a cold water bath. To a separate dry dram vial, add dichloromethane (0.5 mL) and trifluoroacetic anhydride (TFAA, 3.54 mmol). TFAA hydroyzes rapidly in moist air, so make the transfer quickly. Using a needle, add the TFAA solution dropwise to the aniline solution. You will want to vent the septum with an additional needle. Heat is produced in the reaction. If the addition is too rapid, the methylene chloride starts to reflux and fumes are emitted. After the addition is complete, allow the reaction to stir at ambient temperature for 10 min. Remove the septum from the reaction vial and, in the hood, concentrate the solution on a warm sand bath under a slow stream of air. The crude 2,2,2-trifluoroacetanilide intermediate is obtained as a white powder. Cap the vial. The crude material is not purified further, but rather used directly in the next reaction of the sequence without further characterization. Label the vial, seal the cap with parafilm, and place in the fridge until next week.Day 2 (3/26):Remove your product from the fridge from week 1. Carefully transfer your product and stirbar to a 5-10 mL round-bottom flask, and attach a microscale reflux condenser (you do not need to hook up water to the condenser). Very carefully measure out chlorosulfonic acid (13.7 mmol) into a dry dram vial. CAUTION: Chlorosulfonic acid is a very corrosive substance. It reacts violently with water and causes serious burns on contact with the skin. Dispense the reagent in the hood and wear gloves. Very carefully and slowly add the chlorosulfonic acid to the reaction vessel through the condenser by Pasteur pipet....
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