Synthesis Flashcards
What happens when an organic reaction takes place?
Bonds in the reactant molecules are broken and bonds in the product molecules are made.
What is the process of bond breaking known as?
Bond fission
What are the two types of fission
Homolytic and Heterolytic
Homolytic fission results in the formation of
two neutral radicals
Heterolytic fission results in the formation of
two oppositely charged radicals
Heterolytic fission occurs when…..
when one atom retains both electrons from the σ covalent bond and the bond breaks unevenly
Heterolytic fission normally occurs when ……….. bonds are broken
Polar covalent bonds
Reactions involving Heterolytic fission tend to result in……
far fewer products than reactions involving homolytic fission, and so are better suited for organic synthesis.
Homolytic fission occurs when…….
Each atom retains one electron from the sigma covalent bond and the bond breaks evenly
Homolytic fission normally occurs when ……….. bonds are broken
non-polar covalent bonds
Reactions involving homolytic fission tend to result in……
the formation of very complex mixtures of products, making them unsuitable for organic synthesis.
Single headed arrow indicated
movement of one electron
Double headed arrow indicated
movement of two electron
What do the tail and head of an arrow determine
Tail - Source of Electrons
Head - Destination of Electrons
Two single-headed arrows starting at the middle of a covalent bond indicate
Homolytic bond fission is occurring
A double-headed arrow starting at the middle of a covalent bond indicates
heterolytic bond fission is occurring
An arrow drawn with the head pointing to the space between two atoms indicates that a
Covalent bond will be formed between those two atoms
In reactions involving heterolytic bond fission, attacking groups are classified as…..
Nucleophiles or Electrophiles.
Charge and examples of Neucleophiles
Negatively charged ions or neutral molecules that are electron rich, such as Cl , Br , OH , CN , NH and H2O
Neucleophiles are attracted to……
atoms bearing a partial (δ+) or full positive charge
Neucleophiles can form a new covalent bond by….
Donating an Electron pair
Charge and examples of Electrophiles
Positively charged ions or neutral molecules that are electron deficient, such as H+ , NO2+ and SO3
Neucleophiles are attracted to……
atoms bearing a partial (δ+) or full positive charge
Electrophiles can form a new covalent bond by….
Accepting an Electron pair
