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1. |
The 1H NMR spectrum of 2-heptanone is given below. The protons attached to C7 appear as a triplet at d 0.97, the protons attached to C6 appear as a multiplet at about d 1.3 and the protons attached to C5 appear as a multiplet at d 1.4ppm. The remaining signals can be assigned by inspection. |
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i) |
Produce a sketch of the 1H COSY spectrum for this molecule showing the expected diagonal and off-diagonal peaks. |
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ii) |
In the 13C spectrum of 2-heptanone, the carbon resonances appear at - C1 : d 29; C2 : d 20; C3 : d 43; C4 : d 32; C5 : d 24; C6 : d 23; C7 : d 13 ppm from TMS. Using the 1H assignments given above, draw a sketch of the 1H - 13C Heteronuclear Shift Correlation (HSC) spectrum showing the position of the cross peaks you would expect to see. |
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2. |
The schematic 1H COSY spectrum of 2-hexanone is given below. Using the COSY spectrum, assign the 1H NMR resonances of 2-hexanone, i.e. establish which resonance belongs to which specific H site in the molecule. Answer |
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3. |
Schematic 1H COSY and a 1H - 13C HSC spectrum for the organometallic complex (1) are given below. Explain how the COSY and the C-H correlation spectrum could be used to assign the 1H and 13C spectra of the molecule, i.e. establish which resonance belongs to which specific C and H site in the molecule. Answer |
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