Synthesis

Question 1

When an organic reaction takes place, ________ in the _______ ________ are _______ and bonds in the _________ molecules are ______. The process of bond breaking is known as ________ _________.

Answer 1

When an organic reaction takes place, bonds in the reactant
molecules are broken and bonds in the product molecules are made.
The process of bond breaking is known as bond fission.

Question 2

What are the two types of bond fission?

Answer 2

Homolytic fission and Heterolytic fission

Question 2

Describe Homolytic fission

Answer 2

Homolytic fission:

♦ results in the formation of two neutral radicals
♦ occurs when each atom retains one electron from the σ covalent
bond and the bond breaks evenly
♦ normally occurs when non-polar covalent bonds are broken

Question 3

Reactions involving homolytic fission tends to result in the formation of?

Answer 3

Reactions involving homolytic fission tend to result in the formation of
very complex mixtures of products, making them unsuitable for
organic synthesis.

Question 4

Describe Heterolytic fission

Answer 4

Heterolytic fission:

♦ results in the formation of two oppositely charged ions
♦ occurs when one atom retains both electrons from the σ
covalent bond and the bond breaks unevenly
♦ normally occurs when polar covalent bonds are broken

Question 5

Reactions involving heterolytic fission tend to result in ____ ______ _________ than reactions involving _________ _________, and so are better suited for ________ __________.

Answer 5

Reactions involving heterolytic fission tend to result in far fewer
products than reactions involving homolytic fission, and so are better
suited for organic synthesis.

Question 6

What does a single arrow indicate?

Answer 6

a single-headed arrow indicates the movement of a single
electron

Question 7

What does a double arrow indicate?

Answer 7

a double-headed arrow indicates the movement of an electron
pair

Question 8

In reactions involving heterolytic bond fission, attacking groups are classified as either ________ or ___________.

Answer 8

In reactions involving heterolytic bond fission, attacking groups are
classified as nucleophiles or electrophiles.

Question 9

What are Nucleophiles?

Answer 9

Nucleophiles are:

♦ negatively charged ions or neutral molecules that are electron
rich, such as Cl , Br , OH, CN,
NH and HO
♦ attracted towards atoms bearing a partial ( ) δ+ or full positive
charge
♦ capable of donating an electron pair to form a new covalent bond

Question 10

What are Electrophiles?

Answer 10

Electrophiles are:

♦ positively charged ions or neutral molecules that are electron
deficient, such as
H+, NO2+ and SO3
♦ attracted towards atoms bearing a partial ( ) δ− or full negative
charge
♦ capable of accepting an electron pair to form a new covalent bond