~JL~t.f.:k~ 107 ~Jf-&,?;~±J)I~t~A~t~~

i FIT J)I #JL~1J : 1. ~# ~ Ffc. LJ #Jl , T #Jl

~t~# § ( 1~~!!1) : ;If ~1t.~(0502 , 0706)

#_l_O_]i • J_l_Ji

Part 1 ,-,~,'! (70%)

1. Are the following pairs identical, enantiomers, diastereomers, or constitutional isomers? (1 % each)

F

COOH COOH H1C'r:> H3C ~p a. )<,H and H1~~0H

d. and 't>-CH3

and

HO CH3 I

H3C F

F

''1a H~ &CH, Cl'C a b. ,?' a and e. and h. F~ and

a HiC COOH

Cl H3C _,.CH3

~ Cl

C. )=J and • :~, r. and ~ H3C CH3 a

2. When fumarate reacts with D20 in the presence of the enzyme fumarase, only one isomer of the product is formed, as shown here. Is the enzyme catalyzing a syn or an anti addition ofD20? (4%)

-ooc H \C=CI I \

H coo-fumarate

fumarase coo­

oo+H D-t-H

coo-

3. Number the following compounds in order of increasing pKa value. (Number the most acidic compound 1.) (4%)

0 q ~ 4 0 0

F, ,

~

COOH

~F Cl CH3

l@iLm-*;ktt 107 ~lf--li_Z~±JJI;fft~A~t~~

~ tJt J)l #Ji ;i1J : !!_ 4rf4-$ ric. 0 #Ji , T #Ji

~1~14- § ( 1~~~) : ~ ~1t.$(0502 , 0706))

#_l_O_J{ , J_2_J{

4. Using cyclohexanone as the starting material, describe how each of the following compounds can be synthesized: (2% each)

a. 00H d. 0NH2 g. 0CH=CHz

e. 0CH2NH2

h. 0 (show two m:thods)

f. 0N(CH3)i 0CH,CH3

L (show two methods)

5. A compound with molecular formula CsH1o02 gives the following IR spectrum.

8

When it undergoes acid-catalyzed hydrolysis, the compound with the 1H NMR spectrum shown below is formed. Identify the compounds. (6%)

• G < • ~ > • <

; : ; : : ; : ;

: t : ; ; ~ :

· : : ; :; !:·; j;

:

. ' < • • ' • ' • ~ K > < • > • < .

7 6 5

; i : : ; ~ : < • • > •• ' >. . . , .... , . . . . . , •• < ', •·

; ; ; '. · i• .. " , • ' • > •• > . ~ . ' , . ' ' t ,, , • '.' + ' .••• > •• • ,

¼1 I I: ; '.; i ,. : : :

. ... . ', , • , • <.' . • , i:; ; '. :;: 0

: ; ; ; : '. "

4 3 5 (ppm)

----- frequency

> ••

' .

2

><• I><> . .

···r ·· ; : ~ ; ;· '. : ' .. ,,,. , '.'' '. ' . • < •• • ' .

!2 'I' : : : : > •• • • ' •• < • < I ~ >

I

: : ; :

0

[@ JL * * k $ 107 $ ~ lt ~J! ± J)I ;ilf t;l(A $ -t;I( ~

~ rJT .iJI tJl>i'l : .± 4r# !f: r~ ~ iJi , T tJl

~"t~# § ( 1t~~) : 1f ¥\1t.!f:(0502 , 0706)

#_l_O_Ji • 11;_3_Ji

6. Propose a mechanism that accounts for the formation of the product. (6%)

0 HCI 'II

- ..,A._OCH3

7. a. How could you use IR spectroscopy to determine whether the following reaction had occurred? (3%) b. After purifying the product, how could you determine whether all the NH2NH2 had been removed? (3%)

0 II

Ve,

H #

8. Propose a mechanism for the following reaction: (6%)

9. What reagents are needed to accomplish the multistep transformation shown below? (4%)

10. Which reactant in each of the following pairs undergoes an elimination reaction more rapidly? Explain your choice. (2% each)

or

or

8r

Ii .IL 5t *A.~ 107 ~ ~ J.t ,b~ ± J}l ;:Jf t~A. ~ 1~~

im*km=±• ff•~~k,Tk 3lf t~f4 g C 1~~~) : 11 ;tt11:.•coso2 , 0706)

#_l_O_°A • i_4_°A

11. Purine is a heterocyclic compound with four nitrogen atoms. a. Which nitrogen is most apt to be protonated? b. Which nitrogen is least apt to be protonated? (2% each)

··~N N~ __ J_.~

N N .. H purine

Part 2 -'l!:l! (30%, 1.5% each) ·1. The heats of combustion (-.6.H°) of heptane and 3,3-dimethypentane are 4,817 and

4,809 kJ/mol, respectively. Which statement is true? (A)Heptane is 8 kJ/mol more stable then 3,3-dimethylpentane. (B) 3,3-Dimethylpentane is 8 kJ/mol more stable than heptane. (C) Stabilities cannot be compared since they are not isomers. (D) Stabilities cannot be compared since they give different combustion products.

2. Which of the following has(have) a higher oxidation state of carbon than the carbon in formaldehyde, H2C=O? I. CH3OH II. HCO2H III. H2CO3 (A) I (B) III (C) II and III (D) I, II, and III.

3. The IUPAC name of the following compound is

H H (A) cis-1,2-dimethylcyclohexane. (B) trans-1,2-dimethylcyclohexane. (C) 1, 1-dimethylcyclohexane. (D) cis-1,3-dimethylcyclohexane.

4. Which halogen forms the weakest bond to carbon? (A) F (B) Cl (C) Br (D) I.

r@ .IL 7k ~A$ I 07 $ if:-J.i _z;~ ± JJ1;1f ti(A $ ti(~

i~$-m:±• #*~~-,T-~t~fl- § (ft~~) : 1f ~1t.*(0502 , 0706)

#_IO_]l • J_5_]l

5. In the dehydrohalogenation of2-bromobutane, which conformation below leads directly to the formation of cis-2-butene

CH3 CH3 H H,C$Br H,C$H H3C$-Br H H H Br H CH3

H H H

I II m

(A) only I (B) only II (C) only III (D) I and IL

6. Which of the following would have the fastest rate of reaction to form 4-tert­butylcyclohexene?

KOC(CH3)3

KOC(CH3)3

(A) A (B) B (C) C (D) D.

~ .n.~t•A~ 107 ~if:-£i~ ±.tJI.dft~A~t~~

~ ?Jr J)I IJOi1J : !£ 4r"f4 ~ ~1£ Z:.. IJi , T #Ji

~t~f4 § ( 1t~~) : ~ ~1t.~(0502 , 0706)

#_IO_J • J_6_J

7. What is the product of the reaction below?

+ •• -0

~ (C6H5)3P-CH2

DMSO

(A) 2-methyl-1-pentene (B) 2-methyl-2-propyloxirane (C) 4-methyl-1-pentene (D) 1-pentene

8. Which one of the following is not a resonance form of para-aminobenzaldehyde?

I

(A) I (B) II

+NH2

II

(C) III

m (D) IV

9. The compound shown below is classified as a(n)

(A) lactone. anhydride.

(B) ~-ketoester. (C) diketone.

IV

(D) carboxylic acid

~ Ptr JJI #JI. JJ'l : .1.. ~ l4 ~ f1£. 0 #JI. ' T #JI.

:ilf-t~# El ( 1t~~) : ;/f ~1t.$(0502 , 0706)

#_l_O _J{ • i_7_J{

10. What is the kinetically controlled product in the following reaction?

HBr,-80°C ~

~ ~ ~ Y" Br Br Br Br

A) B) C) D)

(A) A (B) B (C) C (D) D.

11. Which of the following is the product of the intramolecular Diels-Alder reaction

shown below?

0 heat

h' .. 0 0 0 0

A) 00 B) co C) co D) co (A) A (B) B (C) C (D) D.

12. Consider the structure of the AlH 4- ion. The formal charge of Al is

(A) -1. (B) 0. (C) + 1. (D) +3.

13. Which of the following best describes the role of the coenzyme NAD+

(nicotinamide adenine dinucleotide) in biological chemistry?

(A) It reduces other species. (B) It oxidizes other species. (C) It catalyzes

oxidation-reduction reactions. (D) It inhibits oxidation-reduction reactions.

iffl••m=±• #•~~-,T• ~t~# § ( 1~i.~) : 1f ~11:..(0502 , 0706)

#_10_1{, J_8_1{

14. To which side, if any, would the reaction below lie?

(A) to the right. (B) to the left

SNa ~OH + I~

/4

15. Identify the diene used in the reaction shown below.

A) B)

CH3

D)

CH--.,

(A) A (B) B (C) C (D) D

~t~# § ( 1.lc.~~) : ;ff il1tlt(0502 .. 0706)

#_10_1{ • jjt_9_J{

16. Which of the following has the largest Keq for the formation of the hydrate (as

shown below)?

0 Keq HO OH

RAR' + H20 R;z_R: 0 II

A) Cll3CCil3

0 II

B) CH3CCH2Cl

0 II

C) CH3CCHCI2

0 II

D) CH3CCCl3

(A) A (B) B (C) C (D) D

1 7. The compound shown below is the cyclic hemiacetal of

(A) 5-hydroxyheptanal.

(B) 5-hydroxy-2-heptanone.

(C) 6-hydroxy-3-heptanone.

(D) 6-hydroxyheptanal.

• ,.

#_10_~ • j_IO_~

18. The formal charges on the nitrogen and oxygen in the following structures are,

respectively

•• H3C-C N-0:

••

(A) +1, -1 (B) 0, -1 (C) +1, 0 (D) 0,0

19. Which structure is consistent with this lH NMR spectrum?

6 5 4

0 II

A. H -C - CH.,CH,CH ... ~ - .,

0 II

C. HO - C - CH2CH2CH3

(A) A (B) B (C) C

B.

D.

3 2

0 II

·Ji'· ... .. .. . . :: :1••·:::::: :::::: : · .. ~L___________

1

H3C-C -OCH2CH3

0 II

H3CO- C- CH2CH3

(D) D

20. How many degrees of unsaturation are present in this molecule?

~-' U) ..

(A) 1 (B) 2 (C) 3 (D) 4 (E) 5