General method for solving combined spectra question (Mod 8) (1 Viewer)

[SadCeliac]

Hi all,

Does anyone have a general method for structuring and solving 7 marker "find the structural formula of..." questions?

I feel like I just end up taking notes in the working space, usually just putting down the mm from mass spec, writing down each of the troughs in the IR spec and the functional groups, and then looking at environments in C and H NMRs...
Obviously that's how you are meant to do it, but does anyone have a general method to go from there?

E.g., if I know that it is an ester with X Y Z different environments, how would I figure out if it is ethyl ethanoate or methyl propanoate (just an example! sometimes it's obvious ofc).

I'll attach a question below (Ruse 2021 Q32):

H NMR data sheet was attached at the back of the paper but I didn't find it too useful. Question was just to draw the structural formula and justify with working.

My main concern is that the sample answer had huge paragraph chunks explaining each and every part of the spectra, whereas I had just bullet point notes about each spec to help myself work it out (lol I still got it wrong).

Thank you!! <3

Answer to this is.....

 

[carrotsss]

I personally find what the molecule is by annotating over the question. Then, I bullet point (nothing wrong w bullet pointing) every single bit of info which can be gained through each graph, eliminating options as I go until there is only one possible molecule, then just a simple statement saying hence, it must be x