CIE Jun 2016 v1 Paper 2 Q5

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PMT A reaction sequence is shown. 10 reaction 1 H3C CH2 Br bromoethane H3C CH2 CN propanenitrile reaction 4 CH2 OH ethanol H3C reaction H2C CH2 ethene reaction 2 H3C CH2 OH propanoic acid LiAl H4 reaction 3 (a) Complete the diagram to show the mechanism of reaction 1. Include all necessary charges, partial charges, lone pairs and curly arrows. H3C Br CN H3C CN + (b) (i) Give the name of the type of reaction involved in reaction 3.[1] The infra-red spectrum of the propanoic acid produced by reaction 2 is shown. [2] 100 transmittance 50 0 4000 3000 2000 wavenumber / cm1 1500 1000 500 (ii) Describe and explain the main difference between the infra-red spectrum of W and that of propanoic acid.[2]UCLES 2016 9701/21/M/J/16<br /> PMT 11 (c) (i) Reactions 4 and 5 use the same reagent. Give the reagent and conditions needed for reaction 4. reagentconditions[2] (ii) Give the conditions needed for reaction 5.[1] (d) Under appropriate conditions, ethanol and propanoic acid undergo a condensation reaction. (i) State the condition necessary for the reaction.[1] (ii) Draw the skeletal formula of the organic product of this reaction. (iii) Name the organic product of this reaction.[1] [1] Question 5 continues over the page.UCLES 2016 9701/21/M/J/16 [Turn over<br /> PMT (e) V reacts with acidified manganate(VII) ions in two different ways depending on the conditions, as shown in the reaction sequence below. 12 H3C CH2 OH propanoic acid V decolourises bromine water. hot, concentrated MnO4/ H+ cold, dilute/ H+ MnO4 When the acidified manganate(VII) is hot and concentrated, propanoic acid is the only organic product. When the acidified manganate(VII) is cold and dilute, the organic product is T which has two chiral centres. (i) Give the structural formulae of V and T. VT[2] (ii) Identify the types of stereoisomerism shown by V and T. VT[2] [Total: 15] Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge International Examinations Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at www.cie.org.uk after the live examination series. Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.UCLES 2016 9701/21/M/J/16<br />

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