MIDTERM #3 PRACTICE TEST #1

Transcription

1 EM 234 PRITED FIRST AME the exam cover sheets look kind of like this PRITED LAST AME ASU ID or Posting ID Ian R. Gould Person on your LEFT (or Aisle) Person on your RIGT (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 Extra redit /5 e Al Si P S l Ar K a Sc Ti V r Mn Fe o i u Zn Ga Ge As Se Br 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 3300 variable and condition dependent, ca. 2-6 δ peaks Aromatic Ar mainly usually strong R R 2 R Xe Infrared orrelation hart Total (incl Extr / R Interaction Energies, kcal/mol Eclipsing / ~1.0 /Me ~1.4 Me/Me ~2.6 Me/Et ~ R broad with spikes ~ broad ~ R2 broad ~ (cm -1 ) MR orrelation harts TIS IS A M 234 PRATIE EXAM MIDTERM #3 PRATIE TEST # X R 2 R X Gauche Me/Me ~0.9 Et/Me ~0.95 i-pr/me ~1.1 t-bu/me ~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 - 2 - EMISTRY 234, MIDTERM #3 PRATIE TEST #1 AME Question 1 Give the IUPA name for the following compounds. Be sure to use cis/trans, E/Z or R/S where appropriate. Question 2 Rank in order of increasing equilibrium constant for formation of an acetal with a brief explanation. Draw the expected acetal for one of the reactions (only), it does not matter which one. A Me + (cat.) B Me + (cat.) F F Me + (cat.) Question 3 Give the alkyl bromide and the carbonyl compound you would use to synthesize the following alkene in a Wittig synthesis and show all steps and reagents/conditions Ph

3 EMISTRY 234, MIDTERM #3 PRATIE TEST #1-3 - AME Question 4 For each reaction Provide the missing reagents/conditions or major organic products as appropriate, pay attention to stereochemistry including racemic mixtures unless specified b) Unless otherwise indicated... State whether the VERALL reaction is Addition, Elimination, Substitution or Rearrangement State whether the reaction is oxidation, reduction or neither Briefly explain whether the a solution of the product would be optically active or not Zn(g) l, 2 b) 1 Equiv. ( 3 ) 2 l (cat.) ignore stereochemistry/optical activity ignore oxidation/reduction ignore addition/elimination etc c) a 2 r 2 7 / 2 S 4 ignore stereochemistry/optical activity ignore addition/elimination etc. d) /l All 3 ignore stereochemistry/optical activity ignore oxidation/reduction etc. e) 3 + ignore stereochemistry/optical activity ignore oxidation/reduction ignore addition/elimination etc

4 EMISTRY 234, MIDTERM #3 PRATIE TEST #1-4 - AME Question 5 Draw the complete arrow pushing mechanism for the following reaction. Indicate the Lewis acid/base at each step, and if they are also Brønsted acids bases. Add non-bonding electrons as necessary. Draw the ALL important resonance structure of the intermediates 3 Ts (cat.) Question 6 Rank the following in terms of increasing rate of reaction with PhMgBr. Give a BRIEF explanation and AME the three functional groups A B < <

5 EMISTRY 234, MIDTERM #3 PRATIE TEST #1-5 - AME Question 7 Show how you would make the target molecules from the provided starting structures. Show all intermediate structures, do not show any mechanisms 3 Br 2 2 b)

6 EMISTRY 234, MIDTERM #3 PRATIE TEST #2 START F PRATIE TEST #2-2 - AME Question 1 Give the IUPA name for the following compound. Be sure to use cis/trans, E/Z or R/S where appropriate. Question 2 Rank the following in terms of increasing rate of electrophilic aromatic substitution, e.g., reaction with 3 / 2 S 4. Give a BRIEF explanation A B < < Question 3 Give the product of complet acid catalyzed hydrolysis of the following structure 3 +

7 EMISTRY 234, MIDTERM #2 PRATIE TEST #2-3 - AME Question 4 For each reaction Provide the missing reagents/conditions or major organic products as appropriate, pay attention to stereochemistry including racemic mixtures unless specified b) Me All 1. 3 l 2. Zn/g/l/ 2 c) 3 3 d) Me 2 e) S S Ph 2 3

8 EMISTRY 234, MIDTERM #3 PRATIE TEST #2-4 - AME Question 5 Give a full curved arrow-pushing mechanism for the following reactions, show where every proton goes to and comes from (no + + /- + ) and indicate the Lewis and Bronsted acids/bases at each intermolecular step, include important resonance contributors for all intermediates, give the number of steps in your mechanism. l/ 2 b) a/ 2

9 EMISTRY 234, MIDTERM #3 PRATIE TEST #2-4 - AME Question 6. Show how you would synthesize the target componds on the right from the starting compounds on the left. Show reagents and conditions, and the structures of important intermediate compounds. Do not show any (arrow pushing) mechanisms.

10 EMISTRY 234, MIDTERM #3 PRATIE TEST #3 START F PRATIE TEST #3-2 - AME Question 1 Give the IUPA name for the following compound. Be sure to use cis/trans, E/Z or R/S where appropriate. Question 2. Give a complete curved arrow pushing mechanism, and... 1) Indicate the Lewis acid/lewis base (LA, LB) at each step as appropriate, and whether they are also Brønsted acids/bases (LA/BA, LB,BB), show where every proton comes from and goes to (no + + /- + ) 2) GIVE TE UMBER F STEPS I YUR MEAISM l

11 EMISTRY 234, MIDTERM #3 PRATIE TEST #3-3 - AME Question 3 For each reaction 1) Provide the missing reagents/conditions or major organic products as appropriate 3 + Ph b) /l Br All 3 Ph c) MgBr 3 + d) Br 1. PPh 3 2. BuLi 3. e) ignore stereochemistry 1 Equiv Ḣ Ts (cat.)

12 EMISTRY 234, MIDTERM #3 PRATIE TEST #3-4 - AME Question 4 Rank the following in terms of increasing frequency of carbonyl stretching vibration in an IR spectrum. To solve this problem you will ened to draw minor resonance contributors and remember that stronger bonds vibrate with higher frequency) 3 A 3 Me 2 B < < 3 Question 5 Give the product of the following reaction. Remember that D represents deuterium, an isotope of hydrogen, that is used to keep track of where hydrogen atoms go in chemical reactions. We did not cover this reaction class, but you should be able to work it out based on what you know about the mechanisms of these reduction reactions 3 1. LiAl D 3 +

13 EMISTRY 234, MIDTERM #3 PRATIE TEST #3-5 - AME Question 6. Show how you would synthesize the target componds on the right from the starting compounds on the left. Show reagents and conditions, and the structures of important intermediate compounds. Do not show any (arrow pushing) mechanisms. 2 Br S 3 b) Br

14 EMISTRY 234, MIDTERM #3 PRATIE TEST #3-6 - AME Question 7 Give a full curved arrow-pushing mechanism for the following reactions, show where every proton goes to and comes from (no + + /- + ) and indicate the Lewis and Bronsted acids/bases at each intermolecular step, include important resonance contributors for all intermediates, give the number of steps in your mechanism cytosine is one of the pyrimidine bases in DA, it can be converted into uracil. if this happens this can be a damage mechanism that could lead to mutation. Assume that this reaction occurs via the usual acid catalyzed mechanisms that we study in class, give a mechanism for formation of uracil from teh provided tautomer of cytosine b) cytosine tautomer 3 + uracil

15 EMISTRY 234, MIDTERM #3 PRATIE TEST #4 START F PRATIE TEST #4-2 - AME Question 1 Give the IUPA name for the following compound. Be sure to use cis/trans, E/Z or R/S where appropriate. Question 2 Rank the following in order of increasing equilibrium constant for formation of a hydrate. Give a BRIEF explanation 3 A 2 B < < Question 3. Rank in order of increasing rate of reaction with, give a BRIEF explanation A B F F (fastest) < < (slowest)

16 EMISTRY 234, MIDTERM #3 PRATIE TEST #4-3 - AME Question 4. For each reaction. 1) Provide the missing reagents/conditions or major organic products as appropriate 2) Pay attention to stereochemistry including racemic mixtures unless specified 2 l (cat.) Br 2 4 b) K/heat Br 2 / FeBr c) F 3 d) ( 3 ) 2 + cat. e) 3 +

17 EMISTRY 234, MIDTERM #3 PRATIE TEST #4-4 - AME Question 5. Show how you would synthesize the target compound on the right from the starting compound on the left. Show reagents and conditions, and the structures of important intermediate compounds. Do not show any (arrow pushing) mechanisms. Br l 2 b) Ph

18 EMISTRY 234, MIDTERM #3 PRATIE TEST #4-5 - AME Question 6 Give a full curved arrow-pushing mechanism for the following reactions, show where every proton goes to and comes from (no + + /- + ) and indicate the Lewis and Bronsted acids/bases at each intermolecular step, include important resonance contributors for all intermediates, give the number of steps in your mechanism b)

19 EMISTRY 234, MIDTERM #3 PRATIE TEST #4-6 - AME Question 7 Rank in order of increasing rate of reaction with a Grignard reagent, giove a brief explanation in terms of nucleophiles and electrophile stregth and tthe factors that control these in this context. 3 F A B D < < < Question 8. Rank in order of increasing rate of electrophilic aromatic substitution at the carbons indicated by the arrows. Give a BRIEF explanation. B A D 3 < < < slowest fastest