OOCC
HOHOC
HHOCH 3 OHA
n important group of organic
reactions consists of those that
involve the transfer of electrons
from one molecule to another. Organic chemists
use these reactions—called oxidation–reduction
reactionsor redox reactions—to synthesize a large
variety of compounds. Redox reactions are also important
in biological systems because many of these reactions produce
energy. You have seen a number of oxidation and reduction reactions in
other chapters, but discussing them as a group will give you the opportunity to
compare them.
In an oxidation–reduction reaction, one compound loses electrons and one com-
pound gains electrons. The compound that loses electrons is oxidized, and the one that
gains electrons is reduced. One way to remember the difference between oxidation
and reduction is with the phrase “LEO the lion says GER”:Loss of Electrons is Oxi-
dation; Gain of Electrons is Reduction.
The following is an example of an oxidation–reduction reaction involving inorganic
reagents:In this reaction, loses an electron, so is oxidized. gains an electron, so
is reduced. The reaction demonstrates two important points about oxidation–
reduction reactions. First,oxidation is always coupled with reduction. In other words, a
compound cannot gain electrons (be reduced) unless another compound in the reaction
simultaneously loses electrons (is oxidized). Second, the compound that is oxidized
is called the reducing agent because it loses the electrons that are used
to reduce the other compound Similarly, the compound that is reduced is
called the oxidizing agentbecause it gains the electrons given up by the other compound
when it is oxidized.
It is easy to tell whether an organic compound has been oxidized or reduced simply
by looking at the change in the structure of the compound. We will be looking primarily(Cu+)(Fe^3 +). (Fe^3 +)(Cu+)Fe^3 +Cu+ Cu+ Fe^3 +Cu++Fe^3 +¡Cu^2 ++Fe^2 +20
More About
Oxidation–Reduction
Reactions
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