CHEM 234, Spring 2015 PRINTED FIRST NAME. Final Exam ASU ID or Posting ID. Ian R. Gould PRINTED LAST NAME

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1 CEM 234, Spring 2015 PRINTED FIRST NAME PRINTED LAST NAME Final Exam ASU ID or Posting ID Ian R. Gould Person on your LEFT (or Aisle) Person on your RIGT (or Aisle) 1 /12 2 /20 3 /25 4 /12 5 /20 6 /64 a) /8 b) /8 c) /8 d) /8 e) /8 f) /8 g) /8 h) /8 7 /8 8 /12 9 /28 10 /10 11 /18 12 /20 13 /36 a) /20 b) /16 14 /40 a) /20 b) /15 c) /15 15 /40 a) /20 b) /20 PRINT YUR NAME N EAC PAGE! READ TE DIRECTINS CAREFULLY! USE BLANK PAGES AS SCRATC PAPER work on blank pages will not be graded... WRITE CLEARLY! MLECULAR MDELS ARE ALLWED D NT USE RED INK DN'T CEAT, USE CMMN SENSE! e Li Be B C N F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba Lu f Ta W Re s Ir Pt Au g Tl Pb Bi Po At Rn Extra Credit /5 Total (incl Extra) /375+5

2 CM 234, Spring 2015, FINAL EXAM NAME Question 1 (12 pts.) Provide IUPAC names for the following structure, do not forget to use E/Z and R/S as appropriate. a) C 2 Question 2 (20 pts.) For each of the structures A, B and C: a) Add the hydrogen atom to the line-angle structure that would be the most Bronsted acidic b) Rank A, B and C in order of increasing Bronsted acidity and give a brief explanation c) for structure A NLY, draw the conjugate base, including all resonance contributors - + A < < B C weakest acid strongest acid

3 CM 234, Spring 2015, FINAL EXAM -3 - NAME Question 3 (25 pts.) For the following acid/base equilibrium: a) draw the curved arrows showing bond making/breaking b) indicate which is the STRNGER and the WEAKER acid and base on each side c) Indicate which acid has the larger and which the smaller pka d) give a BRIEF explanation for your choice of stronger/weaker that includes the phrase "energy of the electrons" N N N N + + e) Indicate which reaction (left to right or right to left) is faster and which is slower and indicate on which side the equilibrium lies f) Draw a PRPERLY labelled reaction energy diagram, indicate the position of the transition state and include a drawing of the transition state Question 4 (12 pts) Explain why sodium borohydride (NaB 4 ) will reduce a ketone but will not reduce an ester. NaB 4 / NaB 4 / no reaction

4 CM 234, Spring 2015, FINAL EXAM NAME Question 5 (20 pts) Give a curved arrow pushing mechanism for the following reaction For each INTERMLECULAR step, indicate the Lewis acid and base (LA or LB) and whether they are also Bronsted acids and bases (BA or BB) as appropriate You MUST show where every proton comes from and goes to, no abbreviated + + /- + notation you do NT need to show resonance contributor for the intermediates in this case! C C 3 Extra Credit Question (5 pts). Which functional group formed the basis of the new "twoelectron sensitizer" molecule that enhances the speed of motion picture film? amine ester amide aldehyde

5 CM 234, Spring 2015, FINAL EXAM NAME Question 6 (64 pts) Provide the missing major organic products for the following reactions. Do not forget to include stereochemistry as appropriate and INDICATE ANY RACEMIC MIXTURES. a) 2 N Ph Cl 1 equivalent NMe 2 b) + heat C 2 C 3 1 equivalent c) + cat. d) Cl cat. heat Br 1. NaCN e) 2. LiAl f) MgBr

6 CM 234, Spring 2015 FINAL EXAM NAME Question 6, Contd... Provide the missing major organic products for the following reactions. Do not forget to include stereochemistry as appropriate and INDICATE ANY RACEMIC MIXTURES. g) excess + Ph 1. Na h) MgBr Question 7 (8 pts) Give the reactants AND reagents/conditions that would allow you to synthesize the following structure in an Aldol condensation. Question 8 (12 pts) Give the product of complete hydrolysis of the following structure (hydrolyze all functional groups that can be hydrolyzed) C N 3 + heat

7 CEMISTRY 234, Spring 2015 FINAL EXAM NAME Question 9 (28 pts) The purpose of this question is to determine whether the provided product is allowed or forbidden using FM theory a) First, give the curved arrow-pushing describing product formation Me Δ + Me Pr Me Pr A B Me b) Now, state whether the reaction to give the PRVIDED product (which may or may not be allowed) is suprafacial or antarafacial with respect to both reactants A and B reaction to give the PRVIDED product was (supra or antara) for reactant A reaction to give the PRVIDED product was (supra or antara) for reactant B c) n TP F TE structures below, draw the M for reactant A and the LUM for reactant B M A Pr d) USING F.M.. theory, state whether the ALLWED product of this reaction (which may or may not be the one that is provided) should be formed in a suprafacial/suprafacial or suprafacial/antarafacial reaction. e) Is the PRVIDED product allowed or forbidden? Me Me LUM B Question 10 (10 pts.) Indicate which of the following two structures A and B you would expect to be the stronger Bronsted BASE, and give a brief explanation that includes the term "energy of the eletrons". Assume that both structures are completely FLAT. A B

8 CEMISTRY 234, Spring 2015 FINAL EXAM NAME Question 11 (18 pts.) Give a curved arrow-pushing mechanism for the following reaction that shows formation of BT products. There are no other reagents or catalysts in this reaction and the solvent is not involved. SW WERE EVERY PRTN CMES FRM AND GES T (no + + /- + ). Indicate the Lewis acid and base (LA or LB) at each INTERMLECULAR step and whether they are also Brønsted acids and bases (LA/BA or BA/BB) N 2 + N acetominophen - painkiller + Question 12 (20 pts.) Give a curved arrow-pushing mechanism for the following reaction. You can use the abbreviated + + /- + notation, but include all important resonance contributors for the intermediates. + heat cat.

9 CM 234, Spring 2015, Final Exam NAME Question 13 (36 pts.) Give a curved arrow-pushing mechanism for the following two reactions SW WERE EVERY PRTN CMES FRM AND GES T Indicate the Lewis acid and base (LA or LB) at each INTERMLECULAR step and whether they are also Brønsted acids and bases (LA/BA or BA/BB) a) 3 + heat + b) 2 /Na

10 CM 234, Spring 2015 FINAL EXAM NAME Question 14 (50 pts.) Show how you would make the target componds on the right from the starting compounds on the left. Show reagents and conditions where appropriate, and the structures of important intermediate compounds. Do not show any (arrow pushing) mechanisms. For question a) you must indicate steps that require separation of isomers. a) S 3 C 3 N 2 TE NEXT TW SYNTESIS PRBLEMS, b) and c), USE NLY REACTINS FRM TE "MINIMAL SET F REACTINS" PRVIDED RECENTLY N TE CLASS WEB PAGE! b) ignore stereochemistry c) Br

11 CM 234, Spring 2015 FINAL EXAM NAME Question 15 (40 pts.) Synthesize the (target) molecule on the right from the starting molecule the left. this can not be done in one reaction. Give reagents and conditions and the intermediate molecules at each step. Do not show any mechanisms or transient intermediates. a) N b)