Chapter 18: Q42P (page 967)

Sketch the expected proton NMR spectrum of 3,3-dimethylbutanal.

Short Answer

Expert verified

The expected proton NMR spectrum of 3,3-dimethylbutanal is as follows:

Step by step solution

Step-1. Proton NMR spectrum:

Nuclear magnetic resonance is concerned with the magnetic properties of certain nuclei. The sizes of peaks in the spectrum gives important information about the number of hydrogen atoms in environment. Height of the peak doesn’t matters, what matters is the ratio of the areas under the peaks. The horizontal scale depicts chemical shift in parts per million. The further to the left the peak is, the more downfield it is. NMR spectra are usually measured using solutions of the substance being investigated.

Step-2. Proton NMR spectrum of 3,3-dimethylbutanal:

Proton NMR spectrum of 3,3-dimethylbutanal is depicted below with splitting pattern and chemical shifts of hydrogen atoms. The hydrogen atom connected to carbonyl carbon have highest value of chemical shift (9.5-9.6) due to more deshielded environment and its splitting pattern would be triplet due to adjacent two hydrogen of methylene group. The two hydrogen of methylene have chemical shift value around 2.1 and its splitting pattern would be doublet due to presence of one hydrogen which is connected to carbonyl group. Nine hydrogens of tertiary butyl group shows singlet and chemical shift value around 1.0.