7/25/2019 Key Final Exam 2040 1516

1/8

45

1

^6 ^^ ^ k.m^ l ^^s

>e

.P

^r

^oH c

Providethemajor organi c p roduct s)for thefol low ing reactions. Drawthe

sothat stereochemistry isobviousandindicateifenantiomersareformed.

enantiomer formationand thereisnone,you

will

notreceive

full

credit.

carbonsas well,you

w i l l

notreceiveanycredit i f your carbon countis o

structure

is

not correct.

0

II

H2Cr04 H2O ^ ^ C

7/25/2019 Key Final Exam 2040 1516

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7/25/2019 Key Final Exam 2040 1516

3/8

2.

C H ; , C H 2 C H 2 B r

(2

p r o d u c t s )

P r o v i d e l U P A C names for the fo llo wing co mpo und, s p ecifying s tereochem

necessary . )

P r o v i d e t h e s t r u c t u r e o f t h e c o m p o u n d c o r r e s p o n d i n g t o t he f o l l o w i n g c

name.

Ethylene glycol

1^0 ol-l

Houi

m(xny

i f^^s

did

1

ioJk aLttx

cohAt^orJ mamas

7/25/2019 Key Final Exam 2040 1516

4/8

T r i c h l o r i n A is a natural product w i t h si gnifi cant toxi ci ty against breast

ome steps

i n apartial synthesis are shown below.

a m o n o anion a dianion

(pull o ff most acidic proton)

1. E H O H

uivalent

H- CHjCCH^)/

y^

3 ^ > D

l i ^ ^ ^

/

CH2

a. Cir cl e the tw o most acidic proton s i n the starting mater ial .

b. Provi de thereagents A, C, E and the interm ediates B and D.

C: ^ ^ ^

E:

c. The diani on Breacts specifical ly at one of

its

nucl eophi lic sites.

n u c l e o p h i l i csites on the diani on and EX PE AI N wh y the reaction is so

fo r

one site. ,

^ li

7/25/2019 Key Final Exam 2040 1516

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20

4

Compare the followingsets o f reactions and circle the one that

will

be fast

reason for yourchoice. NO TE : I f you do not provide the correct reason, or

w i l l notreceive full credit for your selection. These are like problems we

a.

A. C H 3 C H 2 C H 2 B r + N a X W

-oMsrr

C H 3 C H 2 C H 2 C N + Na'Br-

2.

C H 3 C H C H 3

+

N a A N -

Br

DMSO

C H 3 C H C H 3

+

Na ' Br -

C N

^

Reason:

S Q ' ^ S oA)^'^^a./^ f

ClS^^ ^

b.

1.

C H 3 C H 2 C H 2 Br

+

C H s O N a *

H2O

CH3CH2CH2OCH3

+

Na^Bf

2. C H 3 C H 2 C H 2 Br + CH3SNa*

Rea^om-

5. Problem 11-55c.

Propose

an arrow pushing mechanism for the fol low in g reaction. Hint: the thi

pinacol rearrangement product. 7 /)c5^ uuC^rc ^10 / tfClprCSSK/lf

o

7/25/2019 Key Final Exam 2040 1516

6/8

Ethylene oxid e oxira ne) is a valuable building block for organic synthe

carbon of its two carbon skeleton has a func tion al group . The key to rec

structural

unit

derived

from

ethylene oxide is the

presence

o f Nu -CHj-CH^

The fol low ing is aseries of reactions startingwith ethylene oxide.

Ple

necessary

reagents

A-F , for

each

conversion.

H , C N

\

H

O H

O H

B

H 3 C N

V

D

B:

IX

O H

O H

H 3 C N

\

H3 C N O

H 3 C N S

C:

D :

E:

dec

F:

7/25/2019 Key Final Exam 2040 1516

7/8

24

7 Provide syntheses of the fo ll ow in g compounds using the starting materi

othernecessary inorganic and organic reagents. Be sure to show a ll pert

compounds and you w i l l

receive

credit for them . This is not a mechanism

arrow-p ushing . I f you do not kno w the structure of

cyclohexene

or

a

may ask for them but w i l l

lose

points. WO RK BACKWARDS

a.

H int:

the last

step

is an oxidation.

Cyclohexene

^ [

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/

24

8. Man y organic reactions can be broadl y classified asacid base reactions,

electrophile/nucleophile. It is very important do be able to recognize th

in molecules as well as comparative acidities.

A l l

of the compounds below can react as acids.

C i

1 2 3 4

X^

a. C ircle the most acidic proton oneachcompound.

b.

Without

u sing a table, ra nk ^ h e compounds i n order o f increasing ac

the

left).

c. The fo ll ow in g reaction is kn own to occur:

O H + PB n

B r

Identify the Nuc leop hil ic Nu) and Electr ophi lic E) sites in the startin

e a ,

of

g p

r