Click on any peak for help in interpreting this spectrum.

This group of peaks is best described as a "multiplet", area 1, indicating that it corresponds to a CH which is split by more than one adjacent hydrogens. The chemical shift (d 5.7) is in the alkene region.

This group of peaks is also best described as a "multiplet", area 2, indicating that it corresponds to a CH₂ (or two non-equivalent CH groups) which again shows complex splitting. The chemical shift (d 5.0) is also in the alkene region.

The peak is a singlet, area 9, indicating that it corresponds to nine identical hydrogens (three isolated CH₃ groups). 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 31) is in the "simple alkane" region.

The peak is a singlet, indicating that it corresponds to a carbon bearing no hydrogens. The chemical shift (d 45) suggests that the carbon is adjacent to a mild electron-withdrawing group, or may be shifted due to steric effects.

The peak is a triplet, indicating that it corresponds to a CH₂. The chemical shift (d 109) is in the alkene region.

The peak is a doublet, indicating that it corresponds to a CH. The chemical shift (d 149) is in the alkene region and may be shifted further due to steric effects..

The ¹³C spectrum contains four peaks; a quartet at d 31, a weak singlet at d 45, a doublet at d 149 and a triplet at d 108. The quartet most likely represents a relatively simple methyl group, bonded to a carbon, and the singlet most likely represents a carbon with no hydrogens, bonded to a mildly electronegative group. The doublet and triplet are in the alkene region; the triplet is somewhat shielded, perhaps due to a steric effect in the a-position.

3400 cm-1:	no OH or NH present		3100 cm-1:	sharp peak to suggest sp2 CH
2900 cm-1:	strong peak indicating sp3 CH		2200 cm-1:	no unsymmetrical triple bonds
1710 cm-1:	no carbonyl absorbance		1650 cm-1:	strong peak to suggest C=C

The spectrum seems to be consistent with a simple alkene.

Click on any numbered peak for help in interpreting this spectrum.

The peak occurs at m/e = 69, and it is the base peak in this spectrum (the most intense peak) and it represents m-15; loss of a methyl group.

The peak occurs at m/e = 84, and it represents the molecular ion.

The peak occurs at m/e = 73, making this peak m-15 (loss of a methyl group).

The peak occurs at m/e = 87, making this peak m-1 (loss of a hydrogen). Loss of a m/e = 1 is often seen in compounds with acidic hydrogens.

The peak occurs at m/e = 88, which is the molecular weight of the compound, making this the molecular ion (m^.+).

The mass spectrum consists of a molecular ion at 84, and a base peak at m-15 (m/e = 69) which is consistent with loss of a CH₃ group. The spectrum is consistent with a simple molecule which can lose a methyl group to form a stable cation.

C₆H₁₂: MW = 84.16

From the molecular formula, the compound has "one degrees of unsaturation" (one double bond or ring).

The proton NMR has a singlet representing nine equivalent hydrogens (three -CH₃ groups) and two highly split multiplets in the region d 5 - 6 (the alkene region). The singlet strongly suggests the presence of a tert-butyl group (-C(CH₃)₃), while the multiplets suggest a terminal alkene "ABC" splitting pattern.

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IUPAC Name: 3,3-dimethyl-1-butene
Structure: ¹³C NMR: MS: