Organic Chemistry

Problems 129

37. If isomer A is heated to about 100 °C, a mixture of isomers A and B is formed. Explain why there is no trace of isomer C or D.


38. Propose a mechanism for the following reaction:


39. Compound A will not undergo a ring-opening reaction under thermal conditions, but compound B will. Explain.


40. Professor Perry C. Click found that heating any one of the following isomers resulted in scrambling of the deuterium to all three
    positions on the five-membered ring. Propose a mechanism to account for this observation.


41. How could the following transformation be carried out, using only heat or light?


42. Show the steps involved in the following reaction:


43. Propose a mechanism for the following reaction:

H

H+

OH

CO 2 CH 3

+ ∆

O

O

C

C

CO 2 CH 3

+

CO 2 CH 3

CO 2 CH 3

CO 2

H

H

H

H

∆ ∆

D

D

D

H

H

H

H

AB

CH 3

∆

O

H 3 C CH 3

OH

H 3 C

CD 3

C 6 H 5

C 6 H 5

CH 3

CD 3

CH 3

C 6 H 5

100 OC

CD 3

CH 3

C 6 H 5

C 6 H 5

C 6 H 5

CD 3

C 6 H 5 CH 3

C 6 H 5

ABCD