I’ve had a chance to look at the drawings and labels that you compiled for paper 5. I think everyone did a really good job here. I don’t have any complaints, but, as I worked my way through your paperwork, a couple of ideas occurred to me that might prove useful to you ahead of next week’s exam.

First, any compound’s structure is fair game as an exam question, i.e., if a paper refers to a compound by name or by formula or by abbreviation, a careful reader should care enough to figure out what the structure is. I’m not recommending that you draw every compound that a paper refers to (see third point below), but you should know how to draw every compound.

Second, reactions are often described in a paper because the reactions are what the paper is about. However, if a reaction is not described, it’s because the authors assume a careful reader will know this information or will get the necessary information from an appropriate source. Two reactions in this paper deserve a deeper look than what the authors provided:

  • Reaction #1 – the transfer of silylene (tBu2Si) from a silacyclopropane to an α-keto ester. The reaction is catalyzed by AgOTs. The mechanism is not described in this paper (because this is not what this paper is about). A careful reader (like you) is either expected to know this reaction (which seems rather unlikely in this case) or get the information from an appropriate source. In this case, that source would be ref. 4. You are expected to look at every reference that appears to contain vital information.
  • Reaction #2 – the Ireland-Claisen that lies at the heart of Monday’s assignment. I think all of you copied the drawings from the paper to your sheet, but no one mentioned that it showed an impossible transformation or that the configurations of certain atoms weren’t provided. You shouldn’t expect to find errors like this in an exam paper, but you should be testing each of the ideas in a paper out in your own mind, i.e., you should be enough of a critical reader, that you can catch errors if they are present.

Third, notes should serve a purpose. They should lighten the mental load that you carry. They should never make your load heavier.

  • Too many notes are a burden. Notes that duplicate information provided elsewhere are a burden. Notes should be short.
  • Notes that are incomplete, or hard to read, or hard to fathom in the heat of an exam are a burden. Notes should be easy to read and easy to use.
  • Anything that you figure out, but will have a hard time bringing to mind, is a burden. Good notes that describe these kinds of items can lighten your mental load during the exam.
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