Question

AAnswer supplementary questions: 1 to 3

EXPERIMENT XVII - SYNTHESIS OF BENZOCAINE Benzocaine is prepared by the of a carboxylic acid with cthanol. The reaction is: 0 OCH2CH3 + CH CH OH NH NH and Non-Standard Equipment Chemicals absolute ethanol vacuum filter set-up stirring bans concentrated sulfuric acid boiling stones litmus paper 10% sodium carbonate Procedure Dissolve 1.2 g of p-aminobenzoic acid and 12 mL of absolute ethanol in a 100 mL round bottom flask. While swirling, add 1.0 mL of concentrated sulfuric acid dropwise Reflux the resulting mixture for at least 60 minutes with stirring during which any 3. precipitate should dissolve. 4. After allowing the mixture to cool for a couple of minutes, add the contents of the flask to a beaker containing 30 mL of water. Allow the mixture to cool to room temperature and then add slowly 10mL of 10% sodium carbonate being careful to keep the foaming to a minimum. 6. When gas no longer evolves and a white precipitate of benzocaine has formed, continue to add base until the pH is 8. 7. Collect the product by vacuum filtration. Rinse the solid with some cold water a couple of times Data and Calculations 1. Dry the product until next week. 2 Obtain a percent yield. Obtain a melting point 4 Submit your sample for IR analysis. Supplementary Questions What would you predict the 'H NMR and mass spectrum of benzocaine to look like? 2. Afer the sulfuric acid is added, propose a structure for the resulting product What is the gas that is evolved when the bicarbonate is added? Write a chemical equation for this reaction

Answer 1

The peaks in NMR and Mass of benzocaine are shown below-

Que.1 CB) CA) H-NIR 1ntegroinSplttingInterpretalion Peals Label δCPpm) dl 2 H tonu civomatic Po attacheal to ex^jeo attached to nim習 attached to -cHo 6-6 el 2HH 4-31 2LH 4-10 зн 1.3S Mass Molecular ior CMt) Parent loo peals Base peok 께2 = 120 Most stoabla because resonance stabtizatio f turm carbocation