From the molecular formula, the compound has "four degrees of unsaturation" (four double bonds, carbonyls or rings).
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The 13C spectrum contains six peaks, indicating that the molecule has some elements of symmetry. The quartet at 56 and the triplet at 71 represent a CH3 and a CH2 group which are deshielded by electronegative atoms (most likely oxygen); the peaks at 161 - 128 are in the aromatic region; the fact that two doublets and two singlets are observed strongly suggests 1,4-disubstitution.
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The mass spectrum displays a molecular ion, which is the base peak, an m-1 and an m-17, all of which are consistent with a simple alcohol.
The 13C spectrum contains six peaks, indicating that the molecule has some elements of symmetry. The quartet at 56 and the triplet at 71 represent a CH3 and a CH2 group which are deshielded by electronegative atoms (most likely oxygen); the peaks at 161 - 128 are in the aromatic region; the fact that two doublets and two singlets are observed strongly suggests 1,4-disubstitution.
The proton NMR also shows evidence for aromatic 1,4-disubstitution and suggests that the methyl and methylene are isolated and adjacent to electronegative groups. A peak consistent with an alcoholic OH can also be seen.
The IR is consistent with an aromatic alcohol containing no carbonyl group, suggesting that the second oxygen is involved in an ether linkage.
The simplest structure which is consistent with all of these data would be an aromatic compound containing an alcohol group and a methyl ether, situated 1,4 relative to each other.
IUPAC Name: 4-methoxyphenyl methanol
13C NMR Assignments:
Mass Spectrum Fragments:
The proton NMR has two doublets at 6.9, consistent with aromatic 1,4-disubstitution, and three singlets, areas 3, 2 and 1. The singlets at 3.6 and 4.7 are highly shifted and suggest isolated CH3 and CH2 groups adjacent to one or more electronegative atoms or groups. The singlet, area 1, would be consistent with an alcohol.
3400-3200 cm-1: strong OH peak
3100 cm-1: small peak, suggesting possible unsaturated CH
2900 cm-1: strong peak suggesting saturated CH
2200 cm-1: no unsymmetrical triple bonds
1710 cm-1: no carbonyl
1610 and 1500 cm-1: sharp peaks, consistent with aromatic carbon-carbon double bonds
The molecule contains two oxygens, and from the analysis, contains four double bonds, carbonyls or rings. The large number of degrees of unsaturation strongly suggests an aromatic compound (DU = 4).
Structure: