Edexcel Jun 2014 (IAL) Paper 4 Q20

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20 Propanal, CH3CH2CHO, is used in the chemical industry in the manufacture of plastics, and as a disinfectant and preservative. (a) (i) Give the mechanism for the reaction between propanal and hydrogen cyanide in the presence of potassium cyanide. Include the dipole on the carbonyl group. (ii) Classify the type and mechanism of the reaction between propanal and hydrogen cyanide. (4) (2)18 *P42992A01828*<br /> (b) Propanal can be converted into N-methyl propanamide, CH3CH2CONHCH3, in three steps. CH3CH2CHO Step 1 CH3CH2COOH Step 2 compound X Step 3 CH3CH2CONHCH3 (i) The reagent used in Step 2 is phosphorus(V) chloride, PCl5. Identify, by name or formula, compound X. (ii) Identify, by name or formula, the reagent needed for Step 3. (iii) State the number of peaks you would expect in the low resolution proton nmr spectrum of N-methyl propanamide. (1) (1) (1)*P42992A01928* 19 Turn over<br /> (c) Write the equation for the reaction between propanoic acid and propan-2-ol, in the presence of an acid catalyst, showing the structure of the organic product. State symbols are not required. (2) (d) A sample of propanoic acid was reduced to form compound Q. The infrared spectrum of compound Q is shown below. 100 Transmittance / % 4000 3000 2000 1500 1000 500 Use the infrared spectrum to identify compound Q. Explain your reasoning, quoting suitable data. Wavenumber / cm1 (2)(Total for Question 20 = 13 marks) 20 *P42992A02028*<br />

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