Deduce the Structure of the Unknown Compound C₆H₁₂O, Whose IR$\mathrm { C } _ { 6 } \mathrm { H } _ { 12 } \mathrm { O }$

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The Answer is First calculate the degree of unsaturation from the molecular formula. Recall the formula:

U = \frac { 2 C + 2 - H } { 2 }

The unsaturation number is equal to (2*6+2-12)/2 = 1, so there is at least one double bond or ring. The IR spectrum shows a diagnostic peak for hydroxy, but not much else. The NMR spectra confirms the presence of the hydroxy group with a peak at 2.0 ppm that disappears after a D₂O shake. The NMR spectra also show two inequivalent methyl groups, two CH₂ groups and an alkene proton. Since there is only one alkene proton, the unknown compound must be a trisubstituted alkene. The chemical shift of the CH₂ group at 3.6 ppm suggests it is near the hydroxy group, giving the fragment -CH₂OH. Putting the fragments together, the structure must be:
$First calculate the degree of unsaturation from the molecular formula. Recall the formula: U = \frac { 2 C + 2 - H } { 2 } The unsaturation number is equal to (2*6+2-12)/2 = 1, so there is at least one double bond or ring. The IR spectrum shows a diagnostic peak for hydroxy, but not much else. The NMR spectra confirms the presence of the hydroxy group with a peak at 2.0 ppm that disappears after a D2O shake. The NMR spectra also show two inequivalent methyl groups, two CH2 groups and an alkene proton. Since there is only one alkene proton, the unknown compound must be a trisubstituted alkene. The chemical shift of the CH2 group at 3.6 ppm suggests it is near the hydroxy group, giving the fragment -CH2OH. Putting the fragments together, the structure must be: Let's check the structure and make sure it matches the data. The two methyl groups are diastereotopic, so they will not be equivalent. They do not have any adjacent protons, so they are singlets. The CH2 group bonded to the alkene is split by the alkene proton and the adjacent methylene to give an apparent quartet. The alkene is split by the CH2 group, but also by some long-range coupling interactions by protons transmitted by the pi electrons. The remaining CH2 group is expected to be a triplet and the hydroxy proton is a singlet, as expected.$ Let's check the structure and make sure it matches the data. The two methyl groups are diastereotopic, so they will not be equivalent. They do not have any adjacent protons, so they are singlets. The CH₂ group bonded to the alkene is split by the alkene proton and the adjacent methylene to give an apparent quartet. The alkene is split by the CH₂ group, but also by some long-range coupling interactions by protons transmitted by the pi electrons. The remaining CH₂ group is expected to be a triplet and the hydroxy proton is a singlet, as expected.

Deduce the Structure of the Unknown Compound C₆H₁₂O, Whose IR $\mathrm { C } _ { 6 } \mathrm { H } _ { 12 } \mathrm { O }$

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Deduce the Structure of the Unknown Compound C6H12O, Whose IR C6H12O\mathrm { C } _ { 6 } \mathrm { H } _ { 12 } \mathrm { O }C6​H12​O

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Deduce the Structure of the Unknown Compound C₆H₁₂O, Whose IR $\mathrm { C } _ { 6 } \mathrm { H } _ { 12 } \mathrm { O }$

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