Click on any peak for help in interpreting this spectrum.
The peak is a quartet, area 2, indicating that it corresponds to a CH2 adjacent to 3 identical hydrogens (a CH3 group). The chemical shift (d 4.1) suggests that the CH2 is adjacent to an electron-withdrawing group, such as an oxygen.
The peak is a singlet, area 2, indicating that it corresponds to an isolated CH2. The chemical shift (d 3.25) suggests that the methylene is adjacent to an electronegative group.
The peak is a singlet, area 3, indicating that it corresponds to an isolated CH3. The chemical shift (d 2.2) suggests that the methyl is adjacent to an electronegative group (i.e., a carbonyl).
The peak is a triplet, area 3, indicating that it corresponds to a CH3 which is adjacent to a CH2 . The chemical shift (d 1.2) is in the simple alkane region.
The peak is a quartet, indicating that it corresponds to a methyl group. The chemical shift (d 14) is in the "simple alkane" region.
The peak is a quartet, indicating that it corresponds to a methyl group. The chemical shift (d 24) indicates that the methyl group is adjacent to a mild electronegative group.
The peak is a triplet, indicating that it corresponds to a CH2 group. The chemical shift (d 47) indicates that the CH2 group is adjacent to one or more electronegative groups.
The peak is a triplet, indicating that it corresponds to a CH2 group. The chemical shift (d 59) indicates that the CH2 group is adjacent to an electronegative atom such as oxygen.
The peak is a singlet, indicating that it corresponds to a carbon bearing no hydrogens. The chemical shift (d 172) is in the "carbonyl" region, and suggests an acid or ester.
The peak is a singlet, indicating that it corresponds to a carbon bearing no hydrogens. The chemical shift (d 207) is in the "carbonyl" region, and suggests a ketone.
The spectrum seems to be consistent with a simple aliphatic carbonyl compound.
From the molecular formula, the compound has "two degrees of unsaturation" (two double bonds, carbonyls or rings).
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Structure:
The 13C spectrum contains six peaks, indicating that all carbons are unique. The quartets at d 14 and 24 represent relatively simple methyl groups; the triplets at d 59 and 47 represent a CH2 groups bonded to mildly electronegative groups; the singlets at d 207 and 172 are in the carbonyl region, and most likely a ketone or aldehyde (d 207) and an ester (d 172).
3400 cm-1:
no OH or NH present
3100 cm-1:
no peak to suggest sp2 CH 2900 cm-1:
strong peak indicating sp3 CH
2200 cm-1:
no unsymmetrical triple bonds 1710 cm-1:
strong carbonyl absorbance(s)
1610 cm-1:
no peak to suggest C=C
Click on any numbered peak for help in interpreting this spectrum.
The peak occurs at m/e = 43, and it is the base peak in this spectrum (the most intense peak). The molecular weight, m/e = 43, is a common fragment seen compounds containing an acetyl group (cleavage to form H3C
O.+, the acylium ion).
The peak occurs at m/e = 85, making this peak m-45 (loss of ethoxy)
The peak occurs at m/e = 87, making this peak m-43 (loss of acylium ion).
The peak occurs at m/e = 130, which is the molecular weight of the compound, making this the molecular ion (m.+).
The mass spectrum consists of a molecular ion at 130, an m-15 peak at 115, which is consistent with loss of a CH3 group, an m-43 peak (loss of acylium), an m-45 peak (loss of CH3CH2O-), and a base peak at m-43 (m/e = 43) which suggests the formation of an acylium ion (CH3-CO.+). The spectrum is consistent with a molecule which can lose methyl or ethoxy radicals, or can undergo fragmentation to form the acylium cation.
C6H10O3: MW = 130.14
The proton NMR has a quartet coupled to a triplet, indicative of an ethyl group. The CH2 must be adjacent to an electron withdrawing group since it is shifted to d 4.1. The two singlets atd 2.2 and 3.2 suggest isolated CH2 and CH3 groups and the CH2 must be adjacent to one or more electronegative groups.
IUPAC Name: ethyl 3-oxobutanoate (ethyl acetoacetate)
13C NMR: 
MS: 