Unit 3 Aspirin SAC

[Jayz2398]

Hey Guys,

I've completed the synthesis of aspirin experiment (acetic anhydride + salicylic acid with a sulfuric acid catalyst) and we're expected to write results through to discussion in a prac write up (test conditions). I'm planning my discussion/evaluation and have a couple questions.

1. How does sulfuric acid interact as a catalyst? I understand its ability to donate protons and protonate acids (which attracts electrons in OH on alcohols), but I'm not quite sure how it works with acetic anhydride.

2. When cold water was added to a solution of acetic anhydride, salicylic acid and sulfuric acid, an oil was observed before we stirred it. What is this substance? I'm thinking it's sulfuric acid because it's normally oily, but some verification for peace of mind would be much appreciated.

If you guys could explain this to me (diagrams if you can be bothered) that'd be awesome

Thanks,
Jack