Answer Happy

(a) Figures overleaf show 'H, 13C and 19F NMR spectra of a common ionic liquid, 1-ethyl-3-methilimidazolium trifluoromethanesulfonate (structure shown below). All spectra were recorded in d4-methanol. + F3C-S03 (i) Unambiguously assign all signals in all three spectra. To do this, re-draw the structure of this compound on your answer sheet and use lower case letters to assign 'H NMR signals and upper case to assign 13C NMR signals.
(ii) There is a multiplet in the 13C NMR spectrum at ca. 120 ppm. Identify the multiplicity of the signal, explain what nuclei is 13C coupling to, and explain the splitting pattern.
(iii) Explain why signals for the aromatic ring, in both 'H and 13C NMR spectra, are shifted downfield with respect to the signal from the methyl group.
(iv) In a 19F NMR spectrum, in addition to the main signal, there are satellite peaks that integrate to ca. 1% intensity of the main signal. What is the origin of these peaks?
1H NMR NO NOM L ES2 —8.880 <4:38 -3.961 V d a b c ppm 4.3 4.2 e ppm 1.6 1.5 1 11 2 3 ppm 8 6 5 4 3 ż 13C NMR Oroom ONNOL NNNN -136.2 -44.7 -35.2 -14.2 F B E D Ippm 125 120 115 A G ppm 120 100 80 60 40 20
19F NMR -79.9 ppm - 75 -80 -85