1) An unknown organic compound contains carbon, hydrogen and oxygen. It is known that:
• the compound does not contain carbon-to-carbon double bonds (C=C) • the molecular ion peak is found at a mass-to-charge ratio (m/z) of 74
• the ¹³C NMR has three distinct peaks.
a. A small peak in the mass spectrum can be identified at m/z = 75. Explain the presence of this peak

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b) Use the information provided to give two possible molecular formulas for this compound

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c) The ¹H NMR spectrum of the compound shows three sets of peaks with a peak area ratio of 3:2:1. What does this information tell you about the structure of the compound and its molecular formula? Justify your answer by referring to the information given about the peaks in the ¹H NMR spectrum.

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d) There are many structural isomers of this compound. Draw the structural formulas of two possible isomers.

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e) The infra-red (IR) spectrum of the compound is shown below.

i. Identify the functional groups responsible for the absorption peaks labelled A and B in the IR spectrum.

ii. Using the 1H NMR information given in part c. and the IR spectrum provided above, draw the structural formula of the compound.

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