For an aspirin synthesis experiment. 200 mg of salicylic acid and 2 ml acetic anhydride were added to a 25 ml round bottom flask. 5 mg of starting material was diluted in acetone for spotting onto the TLC plate. The reaction mixture was spotted directly without dilution. The plate developed 10:1 hexanes to ethyl acetate and was visualized with a ultraviolet lamp and stained with Iron (III) chloride (1% in MeOH:H2O). 10 ml of de-ionized water was slowly added to the mixture. An ice bath used for crystals formation. The reaction mixture was poured to a 50 ml Erlenmeyer flask. The product dried as the vacuum was on for 10 minutes and finally analyzed for NMR. Mass of purified aspirin product 1.00 (g)
Please answer the following:
Calculate the % yield of the reaction, clearly showing your work.
Carefully copy your TLC plates into your notebook; and then determine Rf values of the starting
material and product. Never submit the actual TLC plates with your lab report, copy them "to scale".
If the TLC solvent was switched to 1:1 H:E, would you expect the Rf values increase or decrease?
Additionally, draw a figure showing how such a TLC plate might look.
Draw a synthesis of the early analgesic phenacetin that employs acetic anhydride, with mechanism.
