Question 1 [16 marks]. The 1H and 13C NMR spectra of compound 1 (C8H12O5) are provided at the     end of the document. FTIR of 1 (neat): n 2840, 2730, 1750, 1730, 1250, 1230, 1160, 1075, 1015 cm– 1 .  Propose a structure for compound 1 that is consistent with the spectral data. Explain how you arrived at your structural proposal.

Question 2 [22 marks]. FTIR, 1H NMR and 13C NMR spectra of compound 2 (C10H9NO5) are provided at the end of the document.

a) Propose a structure for compound 2 that is consistent with the spectral data. Explain how you arrived at your structural proposal.

b) Using labels Ha, Hb, Hc etc. for the hydrogens and Ca, Cb, Cc for the carbons on your proposed structure, assign each signal in the 1H and 13C NMR spectra.

c) Highlight four resonances from the FTIR spectrum that are particularly useful for supporting your structural proposal. Assign each to a particular vibration in your proposed structure.

Question 3 [22 marks]. The EI MS, FTIR, 1H NMR and 13C NMR spectra of compound 3 are provided at the end of the document.

a) Propose a structure for compound 3 that is consistent with the spectral data. Explain how you arrived at your structural proposal.

b) Provide structural assignments for three different fragment ions (not the molecular ion) in the ESI     mass spectrum of 3. Using curly arrows to denote the flow of electrons, draw mechanisms to show how each fragment was generated.

c) Highlight four resonances from the FTIR spectrum that are particularly useful for supporting your structural proposal. Assign each to a particular vibration in your proposed structure.

Question 4 [16 marks]. The 1H and 13C NMR spectra of compound 4 (C13H16O) are provided at the    end of the document. The EI MS of this compound has signals at m/z = 188, 91, 69 (base peak) and 41, and the FTIR spectrum has signals at 3100 and 1696 cm– 1 .

Propose a structure for compound 4 that is consistent with the spectral data. Explain how you arrived at your structural proposal.

Question 5 [16 marks]. The 1H and 13C NMR spectra of compound 5 (C12H14O) are provided at the end of the document. FTIR of 5 (neat): n 3360 (br), 2927, 1453, 1045, 749, 699 cm– 1 .

Propose a structure for compound 5 that is consistent with the spectral data. Explain how you arrived at your structural proposal.

Question 6 [8 marks]. A portion of the 1H NMR spectrum of compound 6 (500 MHz, CDCl3) showing the signal corresponding to Ha is provided at the end of the document.

MeO

6

a) Use Hoye’s method to determine the multiplicity and coupling constants for this signal (show your work).

b) Using labels Hb, Hc etc., assign each of the observed J values to a coupling relationship between hydrogens in compound 6.