EM 234, Spring 2017 Midterm #3 Ian R. Gould MPLETE TIS SETI : Up to TW PITS will be removed for incorrect/missing information! PRITED FIRST AME Answer Key Person on your LEFT (or Empty or Aisle) Person on your RIGT (or Empty or Aisle) lass you are REGISTERED FR (onground or hybrid) The room where most students will take the test for your class, i.e. LS A-191 for onground and PS -152 for hybrid) PRITED LAST AME **YU ARE T ALLWED T TAKE SPARE PIES F TIS EXAM FRM TE TESTIG RM** 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 R 2 R (δ, ppm) variable and condition dependent, ca. 2-6 δ R 11 220 R 10 200 9 180 8 160 7 140 Aromatic R 2 R 2 Xe 6 5 120 100 R 2 Aromatic Ar mainly 8-6.5 2 4 80 R Interaction Energies, kcal/mol Eclipsing / ~1.0 /Me ~1.4 Me/Me ~2.6 Et/Et ~3.1 Infrared orrelation hart small range usually range of values strong broad peak 1600 1660 3300 2720 2820 3000 2 peaks 3100 1680 R 2200 broad with spikes ~3300 1735 2850 2960 1600 broad ~3300 2200 broad ~3000 1710 R2 3500 3000 2500 2000 1650 (cm -1 ) 1500 MR orrelation harts 2 X R 3 60 2 3 2 R 2 R 2 2 40 Gauche Me/Me ~0.9 Et/Me ~0.95 i-pr/me ~1.1 t-bu/me ~2.7 Alkyl X Alkyl 3 > 2 > 1 1 20 3 > 2 > 1 0 0
EM 234, Fall 2017 Midterm #3 Ian R. Gould YU MUST MPLETE TIS PAGE WIT YUR AME (EVE TUG YU ALREADY DID TIS TE VER PAGE) AD ALS GIVE YUR ASU R PSTIG ID UMBER WE EED TIS UMBER BEAUSE YU WULD'T BELIEVE TE UMBER F STUDETS WSE AMES WE A'T READ! PRITED FIRST AME ASWER PRITED LAST AME KEY ASU ID or Posting ID Points by question 1 /13 2 /25 3a /7 3b /7 3c /7 3d /7 3e /7 3f /7 4 /14 5a /22 5b /22 6a /22 6b /14 Points Removed for cover errors /2 Extra redit /5 Total (incl Extra) /175+5 **YU ARE T ALLWED T TAKE SPARE PIES F TIS EXAM FRM TE TESTIG RM**
M 234, Spring 2017, Midterm # - 2 - AME Question 1 (14 pts). Give the IUPA name for the following compound. Be sure to use cis/trans, E/Z or R/S where appropriate. 5 4 3 2 1 5-bromo-(3R)-hydroxypentanal Question 2 (25 pts.) Give a complete arrow-pushing mechanism for the following, indicate the Lews and onsted acids/bases for each ITERMLEULAR step only (LB, LB, BB, BA), AD DRAW ALL RELEVAT RESAE TRIBUTRS FR TE ITERMEDIATES 3 2 3 + + 3 3 or the TER oxygen can be protonated first, etc. 3 3 LB 3 3 3 LA
M 234, Spring 2017, Midterm #3-3 - AME Question 3 (42 pts.) Provide the missing major organic products or reagents/conditions as appropriate, you can IGRE stereochemistry in these problems (a) 2 /l 2 All 3 (b) (c) 1 Equivalent 3 l (cat.) 3 (solvent) 3 + a 3 Zn/g (d) l/ 2 (e) Ts (cat.) (do an intramolecular reaction here) R 1. KMn 4 / - /boil 2 (f) 2. 3 + Question 4 (14 pts.) Reaction A is faster than Reaction B. Give a BRIEF explanation. 3 S 3 3 S 3 2 S 3 2 A B 2 S 2 S 4 4 S 3 electron donating groups are ATIVATIG, which makes reaction at ALL positions faster electron withdrawing groups are DEATIVATIG, which makes reaction at all positions slower
EM 234, Spring 2017 MIDTERM #3-4 - AME Question 5 (44 pts.) Synthesize the (target) molecules on the right from the starting molecules 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. If other isomers are formed at any step then you need to indicate this but you do not need to draw their structures. 2 a) 3 / 2 S 4 separate the isomers 2 l /l/all 3 2 l 2 /Fe 3 2 /Fe 3 2 2 2 l 2 /All 3 2 /l/all 3 l Pd/ l l separate the isomers b) (ignore stereochemistry) l (cat.) ab 4 Et Mg.TF 3 + Mg Mg
M 234, Spring 2017, Midterm #3-5 - AME Question 6 (36 pts.) a) Give a complete arrow-pushing mechanism for the following, indicate the Lews and onsted acids/bases for each ITERMLEULAR step only (LB, LB, BB, BA), but you do T need to show all resonance contributors for intermediates a) l LB/BA l l 2 LB/BA b) Give a complete arrow-pushing mechanism for the following, indicate the Lews and onsted acids/bases for each ITERMLEULAR step only (LB, LB, BB, BA). b) 2 a + Extra credit question (5 pts). n what kind of structure is Agent range based on? Ketone hlorobenzene Benzaldehyde Acetal