The mass spectrum shows that the $m/e$ value for the M peak is $90$. The heights of the M and M+1 peaks are in the ratio $22.1 : 0.7$. Use the M and M+1 peak-height ratio to calculate how many carbon atoms are in a molecule of F.
Suggest the molecular formula for F.
The infra-red spectrum of F was obtained. Use the Data Booklet and your knowledge of infra-red spectroscopy to identify the bond type and the functional group responsible for these three absorptions at $3350\ \text{cm}^{-1}$, $2680\ \text{cm}^{-1}$ and $1725\ \text{cm}^{-1}$.
The mass spectrum shows that the $m/e$ value for the M peak is 90. The heights of the M and M+1 peaks are in the ratio $22.1 : 0.7$.
F was dissolved in deuterated trichloromethane, $\text{CDCl}_3$, and the proton NMR spectrum of this solution was obtained.
Use the Data Booklet together with your answer to part (a)(ii) to complete Table 1 for the proton NMR spectrum of F. The four absorptions in F have been given with their actual chemical shifts at $\delta = 1.4$, $3.9$, $4.7$ and $12.9\,\text{ppm}$.
Describe and explain the splitting pattern shown by the absorption at $\delta = 1.4$.
F was dissolved in $\text{D}_2\text{O}$ and the proton NMR spectrum of this new solution was obtained. Which two absorptions in Table 1 were absent from this spectrum?
Suggest the structure of F.
Molecules of cycloheptadiene, $\text{C}_7\text{H}_{10}$, have a seven-membered ring containing two carbon-carbon double bonds.
Complete the skeletal formulae for two isomers of cycloheptadiene.
Predict the number of peaks that will be seen in the carbon-13 NMR spectra of P and Q.