ORGANIC CHEMISTRY 301

                         EXAMINATION TWO-JUNE 18, 1996

 

I.  (Five points each)  Synthesize the following:

 

 

 

 

 

 

 

 

b.     2-hexyne                                from                1-hexyne

 

 

 

 

 

 

 

c.     1,3-cyclopentadiene                   from               1-bromocyclopentene

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

II.  (Three points each)  Complete the following reactions, include stereochemistry, where applicable.

 

a.    cis-2-pentene    +     D2/cat            ®

 

 

b.    cyclohexene     +    hot KMNO4    ®

 

 

c.       ?                 +   OsO4                  ®

                                                                 

 

d.        ?         +     2-pentyne                 ®        trans-2-pentene

 

 

e.    3-methyl-1-butene   +     HOBr      ®

 

 

f.    cis-2-butene    +    Br2/CCl4              ®

 

 

g.    trans-2-pentene   +   HBr                 ®

 

 

h.    2,3-dimethyl-2-butene     +      ?        ®      

 

 

i.    2-methyl-2-pentene       +     O3/Zn,H+    ®

 

 

j.    1,4-pentadiene      +       HCl            ®

 

 

k.    cyclopentene     +       H2O/H+          ®

 

 

l.    2-pentyne    +    O3/H2O2                  ®

 

 

 

III.  (Fifteen points)

 

                        Compound    A    (C7H10)

 

 

A   +   Br2/CCl4           ®        colorless

 

A    +  KMnO4             ®        brown ppt

 

A    +  excess H2/cat    ®        B  (C7H14)

 

A    +  H2/cat               ®        C  (C7H12)

 

C    +  HBr                  ®        D

 

D    +  alc-KOH          ®        C

 

C    +  O3/Zn,H+           ®        E

 

C   +  O3/H2O2             ®        F

 

A   +  O3/Zn,H+            ®        G   +   H

 

A   +  O3/H­2O2             ®        I    +   J

 

Identify A through J.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IV.  (Four points each)

 

a.  Must all addition reactions of alkenes rearrange?  Explain.

 

 

 

 

 

 

 

 

b.  Why do non-conjugated dienes not have a reaction possibility analogous to the 1,4-addition of conjugated dienes?

 

 

 

 

 

 

 

 

c.  Why are stereospecific reactions useful in organic chemistry, in general.

 

 

 

 

 

 

 

d.  What is wrong, if anything, with the stated reaction: