2006 Organic Chemistry CHE230-001 EXAM 2 Page 2 of 7 1. (5 pts.)1aHFill in the blank below. The name of compound 1a is: (5 ___ )-1,5-dimethylcyclohexene b. (5 pts.) Name compound 1b. Stereochemistry! 1bHClH _____________________________________________ 2. Think about the rate of formation of the following products. HCl /etherHClClClHHHHHHH2a 2b2c 2dHHHHHClHClHHH2e2fHHCl1a a. (10 pts.) HCl adds across the double bond of optically pure 1a. However some of the products form so slow compared to others that we will have a hard time finding them in the product mixture which ones are they? ___________________________________2006 Organic Chemistry CHE230-001 EXAM 2 Page 3 of 7 b. (10 pts.) Will any of the molecules above have identical rates of formation starting from 1a? Explain your answer. Hint: Tell me how the molecules are structurally related and tell me what this has to do with your answer. Short answer! ____________________________________________________________________________________________________________________________________________________ ____________________________________________________________________________________________________________________________________________________ 3. (15 pts.) Draw the products of addition of HCl. Identify which molecules, if any, will be present in equal amounts after the reaction is finished by drawing circles around the molecules and connecting the circles with lines. HCl /etherH3H2006 Organic Chemistry CHE230-001 EXAM 2 Page 4 of 7 4. (10 pts.) OOH I assigned the reading of a brief paragraph entitled “S-ibuprofen versus ibuprofen-racemate. A randomized double-blind study in patients with rheumatoid arthritis.” Why should there be a difference in physical response between S-ibuprofen and ibuprofen-racemate? ______________________________________________________________________________________________________________________________________________________________________________________________________________________________ 5. (10 pts.) Reaction A happens, but reaction B does not. Please explain why. Short answer. ________________________________________________________________________________________________________________________________________________________________________________________________________________________ OOKOH+KOH+KOHOOKOH5A5B2006 Organic Chemistry CHE230-001 EXAM 2 Page 5 of 7 6. (10 pts.) Circle the pair of water molecules in the lowest-energy state. molecules for question 6.OHHOHHHOHHHOHOHHOH 7. (10 pts.) Identify (name/ describe) the HOMO and the LUMO in the reactants of the following SN2 reaction. HBrH3CONa+OH+NaBr HOMO: __________________________________________________________________ LUMO: __________________________________________________________________2006 Organic Chemistry CHE230-001 EXAM 2 Page 6 of 7 8. (15 pts.) Use the chair structure drawn below as a starting point to draw the lowest-energy conformation of molecule 2a (given above in problem 2). Put substituents on the structure; put methyl groups as CH3 and put all H atoms on the structure. 10 pts. awarded for the correct conformation and 5 pts. for the correct enantiomer. Hint: Cl is small compared to
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