1CHE 230 - Organic ChemistryExam 3, April 3, 2002Name Student ID No. Before you begin this exam: First: You are allowed to have a simple model set at your seat.Please put away all other materials. Second: Place your student identification on your desk. Aproctor will come around to check everyone’s ID. Third: Read through the entire exam. Yourgoal, as always, is to score as many points as possible. Do not waste time on problems that youcan’t do if there are others that look easy. Fourth: It is critically important that your answers bewritten in a clear, unambiguous manner. Answers in which your intentions are unclear will notreceive credit. Fifth: READ THE INSTRUCTIONS FOR EACH PROBLEM. You haveuntil 9:50 to complete this exam. There will be no extensions, so budget your time carefully.If you wish to have your exam score posted beside your student ID number in the glass case (1stfloor, CP Building, behind CP-139) with the exam key, place an ‘X’ in this space . Ifyou do not mark this space, your exam score will not be posted.Problem Points Score1. 15 2. 12 3. 12 4. 20 5. 5 6. 7 7. 15 8. 5 9. 6 10. 3 Total 10021. (15 points) Match the energy profile diagrams (A-D) to the reactions below. You canuse one diagram more than once.a) SN1 reaction with Keq > 1 b) E2 reaction with Keq < 1 c) E1 reaction with Keq > 1 d) A rapid E2 reaction with Keq> 1 e) A slow SN2 reaction ProgressGAGProgressBProgressGCProgressGD32. (12 points) Match the energy profile diagrams (1-2) to the reactions below. You can useone diagram more than once.A concerted (single step) kinetically-controlled, exergonic reaction thatcan lead to 2 different products. A concerted (single step) thermodynamically-controlled, exergonicreaction that can lead to 2 different products. A situation where Hammond’s Postulate does NOT hold. GProgress1GProgress23. (12 points) For each of the reactions shown below, indicate if the mechanism is SN1, SN2,E1 or E2.a)BrCH3OHHeatb)BrNaOEtc)CH3OHHeatBr OCH34d)OTs SCH3CH2SNa4. (20 points) Provide the expected organic product from each of the reactions below.Show any relevant stereochemistry. If you believe that no reaction will occur, write “NoReaction.”a)H2SO4, H2Ob)OHClc)CH3OHTsClpyridined)BrCH3tBuO K5. (5 points) Draw a Newman projection for the starting material for the eliminationreaction shown below, in the required conformation for the reaction.BrBr BrNaOEt56. (7 points) Using the data in the table, estimate DH for the reaction below.CH3CH2CH3CH2CH3CH2CH3CH3BrHBrBond Dissociation Energies:H-CH3H-CH(CH3)2H-C(CH3)3Br-CH3100.396.093.370Br-BrH-BrH-OH46.187.6119CH3-CH3CH2=CH2 (p bond only)CH2=CH2 (total)90661727. (15 points) Provide the reagents needed to execute the following reactions. Provide“complete” reagents: If you intend to use bromide ion, specify a reagent such as (NaBr)rather than just Br-.a)ClCNb)Clc)ClH68. (5 points) a-Chloroamines are quite unstable, as they undergo a very facile eliminationreaction. Draw the mechanism and the product of this elimination.N Cl?H9. (6 points) The b-chloroamine below reacts to give the b-aminoalcohol shown. Noticethat the N-C2 bond has been replaced by a N-C1 bond. Draw a viable mechanism for thisreaction.NClHNaOH, H2ONOHH12312379. (3 points) Who is the Hammond Postulate named after? Do not exceed the spaceprovided.END OF
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