A Level Chemistry 9701/22/F/M/16 Q5
5 Some reactions of compound P, C5H8O, are shown.
(a) (i) Give the structures for organic compounds Q, R, S and T.
(ii) Give the systematic name of compound P.
(iii) What would you observe when compound P is reacted with 2,4-dinitrophenylhydrazine (2,4-DNPH)?
(b) Compound U contains a chiral centre and has the same molecular formula as compound P, C5H8O.
• Compound U readily decolourises a sample of bromine water.
• Compound U does not show cis-trans isomerism.
• When compound U is heated under reflux in the presence of excess acidified
potassium dichromate(VI), the organic product gives the infra-red spectrum shown.
Use the information given to suggest a structure for compound U.
Explain your answer.