Organic Chemistry

882 CHAPTER 20 More About Oxidation–Reduction Reactions

65. Show how the following compounds could be prepared, using only the indicated starting material as the source of carbon:

a. d.

b. e.

c. f.

66. Terpineol is an optically active compound with one asymmetric carbon. It is used as an antiseptic. Reaction of terpineol
    with forms an optically inactive compound Heating the reduced compound in acid followed by ozonolysis and
    work-up under reducing conditions produces acetone and a compound whose and are shown. What is the
    structure of terpineol?


67. Propose a mechanism for the following enzyme-catalyzed reaction. (Hint:Notice that Br is attached to the more substituted carbon.)

CH 3

chloroperoxidase

Br−, H 2 O 2

HO HO

CH 3

O

CH 3 CCH^3

O

CCH 3

CH 3

Br

pregnenolone OH

200 180 160 140 120 100 80 60 40 20 0

δ (ppm)

frequency

212

10 9 8765 4 3 210

δ (ppm)

frequency

2.4 2.3 2.2PPM

(^1) H NMR (^13) C NMR
H 2 >Pt (C 10 H 20 O).
(C 10 H 18 O)
OH
OH
H Br
O
O

• CH 2 CH 2
  OH OH
  O
  Br
  O O OH
  H
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