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1. Predict the 1H NMR spectrum. Include the approximate chemical shifts (1’s, 2’s, etc.), the integration, and the splitting (can use “s” for singlet; “d” for doublet; “t” for triplet’ “q” for quartet; and “m” for multiplet, anything more complex than a quartet; or you can instead make a column to list the number of lines). Note: for signals that are symmetry equivalent, do not list them twice.
OO
2. Predict the 13C NMR spectrum. Include the approximate chemical shifts (220-160, 160-100, 100-50, or 50-0) and the splitting if a couple carbon was taken (q, t, d, s).
H O
O
3. Match the following structures with the listed feature IR signals: 1) 1680 2) 1745 3) 3300-3400 4) 3300-2500, 1710
OH
OH
O
OCH3
O O
A B C D
2 Solve the structures for the following. If you get a structure perfect, you will get full credit. If you do not get a structure perfect, you may still get some partial credit. Thus, it is in your interest to show some of you work, make a structure, or tell me what you know for sure. 4. C4H10O IR: 3300-3200 3H, d, 1.10 3H, t, 1.30 2H, m, 1.50 1H, s, 2.90 1H, m, 3.90
3 5. C6H12O2 IR: 1745 13C: 180 (s), 80 (t), 35 (t), 28 (t), 24(q), 19 (q)
Fri Feb 18 19:07:14 2011: Experiment started
Fri Feb 18 19:07:22 2011: BS 1 completed
1.861.89
2.053.00
3.07
ppm1.01.52.02.53.03.54.0
Plotname: Ethyl_Butyrate_PROTON_01_plot02
4 6. C6H12O2 IR: 3300-3200, 1710
13C: 200 (s), 75 (t), 45 (d), 40 (t), 30 (q), 19 (q)
6. C6Hr2O2 IR: 3300-3200, 1710i jc, zoo (s) ,75 ( t ) ,45 (d),40 ( t ) ,30 (q) ' l9 (q)
C6H1 202
5 7. C11H16O IR: Nothing of interest
13C: 150 (s), 135 (d), 130 (d), 120 (s), 68 (d), 40 (t), 25 (q), 20 (q)
7 . c r l H 1 6 0 IR: Nothing of interest' ' c : 1 5 0 ( s ) , r l s t o i , r g o ( d ) , 1 2 0 ( s ) ' 6 8 ( d ) ' 4 0 ( t ) ' 2 5 ( q ) ' 2 0 ( q )
6 8. C4H8O (Two structures are equally acceptable for this problem)
8. C4H8O (Two structures are equally acceptable for this problem)
r . . I t . . . . t . . . r . r . . 1 . . . . t . . . 1 1 . . . . t . | i i l . r , r l . | r | 1 . . I r | i , , r l
1e0 100 80 50 10 20 PPt{ C
I t l I
7 9. C10H14O
9. CroHr4O
1
1. Provide the Name for the Following (6 points)
3. Rank the following, with 1 being highest, or most. (3 points each)
a.
b.
c.
d.
O
OH
O
EtO
O OO
Acidity
OH O CH3Boiling Point
OCH3
O O O Electrophilic Reactivity,When Attacked by a Nucleophile
EtO
O OOH
ORelative amount in the "enol"form at equilibrium
2
4. Synthesis: Draw the feature product of the following reactions (need not show any byproducts). NOTE: In every case, the product should be a stable, isolable product; an “intermediate” structure or something that only forms reversibly in an unfavorable equilibrium will not receive full credit. (2 points each)
a.
b.
c.
d.
e.
f.
O
NH2+H+
Hg2+, H2O, H2SO4
H
CH3O OCH3H2O, H+
O OCH3
OOHHO1.
2. LiAlH4
3. H2O, H+
, H+
H
O
KCN, HCN
Ph
O
H
NaOCH2CH3,
HOCH2CH3(cold, short time)
3
(more synthesis, continued. 2 points each)
g.
h.
i.
j.
k.
l.
O excess Cl2
NaOCH2CH3
O1. 1 LDA
2. BrCH2CH3
OEt
O O 1. NaOEt
2. BrCH3
H Ph
OPh Ph
O1+
NaOCH2CH3,
HOCH2CH3(warmup, long time)
Ph OEt
ONaOEt
Br
O
1. PPh3
2. BuLi3.
4
5. Provide Reagents for the Following Transformations: (4 points each)
a. b.
c. 6. For the following structures, which will be “completely” (>98%) deprotonated by LDA (LiN-iPr2)? By NaOCH3? {Note: it is possible that more than one structure will be depronated.}
a. By LDA? (3 points) b. By NaOCH3? (3 points)
7. Design a synthesis for the following alkene, FROM ALCOHOLS WITH NO MORE THAN 5 CARBONS. (5 points)
OH
O
Br Ph
Ph
OPh
OH OH
Ph H
O
OCH3
O
CH3O OCH3
OOO
DA B C
5
8. Put in the starting materials for the following. (Note: May be only one chemical in several of these cases). (2 points each) a. b. c. d. e.
9. Suggest a possible structure for unknown X, whose formula is C6H8O, given the following information. (5 points) 1) It gives an orange precipitate upon treatment with 2,4-dinitrophenylhydrazine (2,4-DNP) 2) It does not give a silver mirror upon treatment with Tollen’s reagent [Ag(NH3)2
+OH-]. 3) It does react with excess H2/Pt to give C6H10O. 4) It does react with excess Br2 in dichloromethane solvent to give C6H8Br2O. 5) It does not give a positive iodoform test (NaOH, excess NaOH). Summary C6H8O DNP-yes Tollens-no H2/Pt-yes, to C6H10O Br2-yes Iodoform-no
N Phcat. H+
H
OOHNaOCH3
CH3OH
OO
H+
ONaOCH3
CH3OHheat
NaOCH3
CH3OHOCH3
O O
6
10. Provide Mechanisms for the Following Transformations. (3 points each) (Note: in some of these mechanisms, either the reactant or the product may not be a “final product” or an “isolable chemical”. But you should still be able to write the mechanisms.)
O O O OH+ MeOH
NaOH
HOO
O
OH H+
H2O
O O
Ph
1. LDA (LiNR2)
2. PhCH2Br
OCH3
OPh MeOH
NaOMe OPh OCH3
Ph
O
O
NMe2
OH H+
H2O
O
OMe
O
OHH+
H2O
(Note: This process is central to the metabolism of carbohydrates)
1
1. Name the Following or Draw the Structure (2x3 pts each) a. N-methyl-2-phenyl-1-butanamine
b. OH
HO O
H2N 2. Draw the starting materials for the following hydrolysis reactions. (3 pts each)
O
OH1. NaOH, H2O
2. HCl+
a. Ph CO2H
OHHOPh O
MeH
Hb.
1. NaOH, H2O
2. HCl
3. Of the following, which form would actually exist at: (6 points) a) pH = 2 (acidic) b) pH = 7 (neutral) c) pH = 12 (basic)
OH
O
NH2OH
O
NH3O
O
NH3O
O
NH2
PhPh Ph PhA B C D
2 4. Synthesis Reactions. Draw the feature product of the following reactions. (8x3 pts)
Ph NH2Cl
O
1.
2. LiAlH4
NHBr (excess)
NaOH
Ph Br1. KCN
2. LiAlH4
Ph
O MeNH2, NaBH3CN, H+
OH
O
HO
CH3H H+
OEt
O
HO
O
1. NaOH2. SOCl2
3.
Ph OMe
OH2NMe
NH
O1. NaOH
2. H+
3 5. Provide Reagents for the Following Transformations (3x4 pts each)
NH
PhOH
O
OH NH
NH2
O
O
O
6. Compare the following two structural isomers: (8 pts)
a. Which of the two is more basic b. Which of the two is more stable c. What is the hybridization for the nitrogen lone pair in A? d. What is the hybridization for the nitrogen lone pair in B?
NO H N
O
H
BA 7. Rank the reactivity of the following toward substitution, with 1 being most reactive. (3
points)
OMe
O
Cl
O
NMe2
O
O
O O
4 8. Provide Mechanisms for the Following Reactions. (16 points)
Ph Cl
O
Ph NHPh
O+PhNH2
NaOH
Me4N+I- (+ H2O + NaI)Me2N-H + 2 Me-I + NaOH
OO
NH2
O
HONH3
O
OH OH
O
O
HO OH
OH2O, H+H2O, H+
5 8. Which (if any) after being dissolved in diethyl ether, will: (6 points) a) Extract into b) Extract into c) Extract into NaOH/H2O? HCl/H2O? neutral water?
C8H17 OHC8H17 OH
O
C8H17 NH2A B C
9. Rank the following in order of increasing basicity, 1 being most basic, 3 being least (3x2 pts) a. NaOH CH3MgBr CH3NH2 b. Me2NH NH3 CH3CO2Na c. pyridine benzamide (PhCONH2) methylamine 10. Rank the acidity of the following, 1 being most acidic, 3 being least (3x2 pts) a. NH4+Cl- acetic acid 2,2-difluoroacetic acid b. PhCH2OH PhOH PhCO2H c. water p-nitrobenzoic acid benzoic acid