Second Midterm ASU ID or Posting ID

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Barbara Thomasine Greer
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1 EM 234, Spring 2010 PRITED FIRST AME PRITED LAST AME Second Midterm ASU ID or Posting ID Ian R. Gould Person on your LEFT (or Aisle) PRIT YUR AME EA PAGE! READ TE DIRETIS AREFULLY! USE BLAK PAGES AS SRAT PAPER work on blank pages will not be graded... WRITE LEARLY! MLEULAR MDELS ARE ALLWED D T USE RED IK D'T EAT, USE MM SESE! Li Be B F e a Mg e Al Si P S l Ar K a Sc Ti V r Mn Fe o i u Zn Ga Ge As Se Kr Rb Sr Y Zr b Mo Tc Ru Rh Pd Ag d In Sn Sb Te I s Ba Lu f Ta W Re s Ir Pt Au g Tl Pb Bi Po At Rn amine alcohol (δ, ppm) small range range of values broad peak R 2 R R R variable and condition dependent, ca. 2-6 δ peaks Aromatic Ar mainly usually strong Person on your RIGT (or Aisle) 1 / / / / / / / / /18... Extra redit / R R 2 R Xe Infrared orrelation hart Total (incl Extra) / R Interaction Energies, kcal/mol Eclipsing / ~1.0 / ~1.4 / ~2.6 /Et ~ R broad with spikes ~ broad ~ R2 broad ~ (cm -1 ) MR orrelation harts X R 2 R X Gauche / ~0.9 Et/ ~0.95 i-pr/ ~1.1 t-bu/ ~2.7 Approximate oupling onstants, J (z), for 1 MR Spectra Alkyl 3 Y > 2 Y > 1 Y Alkyl ~2 ~10 ~ ~8 ~2 ~7 3 Y > 2 Y > 1 Y 0 0 Aromatic R 2

2 EMISTRY 234, Spring 2010 MIDTERM #2-2 - AME Question 1 (10 pts.) Give the IUPA name for the following compound. Be sure to use cis/trans, E/Z or R/S where appropriate. Et Question 2 (20 pts) GIve a curved-arrow pushing mechanism for the following reaction. Be sure to indicate the Lewis acids/bases (LA/LB) and onsted acids/bases (BA/BB) as appropriate conc. 2

3 - 3 - EMISTRY 234, Spring 2010 MIDTERM #2 AME Question 3 (16 pts) Give the missing products or reactants in the following Diels-Alder reactions. In the missing product, indicate both the relative and the absolute stereochemistry. a) b) F 3 F 3 Question 4 (16 pts.) For the following reactions, provide the missing MAJR REATI PRDUT. Indicate stereochemistry where appropriate. a) Excess Mg b) 1. MPBA 2. Et / l (cat.)

4 EMISTRY 234, Spring 2010 MIDTERM #2-4 - AME Question 5 (34 pts.) For the following reaction, give a full curved-arrow pushing mechanism for formation of BT products and indicate the Lewis acid and base at each step (LA or LB) and whether they are also onsted acids and bases (BA or BB). Include all reasonable resonance contributors for any intermediates AD IDIATE TE MAJR RESAE TRIBUTR IF APPRPRIATE!! A B b) Indicate which product, A or B, would be formed under thermodynamically controlled conditions and which would be formed under kinetically controlled conditions and give a BRIEF explanation of the role of temperature in determining kinetic and thermodynamic control c) Draw an energy diagram for formation of both A and B TE SAME DIAGRAM, clearly indicate which curve refers to formation of A and which to formation of B Extra redit Question (5 pts.) Which kind of structures were discussed as being carconogenic poly-aromatics TF Ethers Dienes

5 EMISTRY 234, Spring 2010 MIDTERM #2-5 - AME Question 6 (25 pts.) Show how you would make the target compond on the right from the starting compound on the left. Show reagents and conditions where appropriate, and the structures of important intermediate compounds. Do not show any (arrow pushing) mechanisms. Question 7 (18 pts) The product of E of the following two reactions A or B is allowed and the other is forbidden a) draw the curved arrow-pushing that describes the bond making/breaking for both reactions A B b) draw a picture of the F.M.. relevant to these reactions on top of each structure below c) Using F.M.. theory, briefly explain which reaction has the allowed product, A or B, include the terms disrotatory and/or conrotatory as appropriate

6 - 6 - EMISTRY 234, Spring 2010 MIDTERM #2 AME Question 8 (18 pts) Shown below is the product of a cycloaddition reaction between two reactants A and B. In this question you are eventually going to determine whether TIS product is allowed or forbidden. FIRST, some questions about the product that is provided... Et Et F 3 F 3 F F 3 3 A B a) Do the curved arrow-pushing that describes bond making and breaking b) Give the number of electrons that are involved in this reaction c) For the product SW (which may or may not be allowed, remember), was the reaction suprafacial or antarafacial as far as the reactant A was concerned? d) For the product SW (which may or may not be allowed, remember), was the reaction suprafacial or antarafacial as far as the reactant B was concerned? W, some questions about the ALLWED reaction for these reactants e) Would an ALLWED reaction between reactants A and B proceed via a uckel or a Mobius transition state. Give a BRIEF explanation f) Is the product shown above allowed or forbidden? Question 9 (18 pts) a) Give the curved arrow-pushing and the allowed product for the following cycloaddition reaction. Pay attention to stereochemistry F 3 F 3 b) TP of the structures as indicated, draw the requested F.M..s and give the total number of π-molecular orbitals and electrons associated with the π-system for each structure. F 3 F 3 draw the LUM total # of π-m..s draw the M total # of π-m..s for this structure = for this structure = total # of electrons in the π- system for this structure = total # of electrons in the π- system for this structure =

Final Exam ASU ID or Posting ID

EM 234, Spring 2008 PRITED FIRST AME PRITED LAST AME Final Exam ASU ID or Posting ID Ian R. Gould Person on your LEFT (or Aisle)!PRIT YUR AME EA PAGE! READ TE DIRETIS AREFULLY! USE BLAK PAGES AS SRAT PAPER