Module 3: Introduction to Reaction Mechanisms Flashcards
unequally divide electrons
heterolysis or heterolytic cleavage
Electrons move from a nucleophilic source (Nu: or Nu:+) to an?
electrophilic site
These are nucleophiles because they contain a carbon with a lone pair
carbanions
The stronger the bond, the ________ its bond dissociation energy
higher
This reaction occur when two reactants add together to form a single product with no atoms “left over.”
addition reaction
bond breaking is?
endothermic
Indicate breaking and forming of bonds using an?
arrowhead
This is the energy needed to homolytically cleave a covalent bond.
bond dissociation energy
This involves only one step the starting material is directly converted to a product no matter how many bonds are broken or formed
One-step/concerted reaction
it describes reaction rates
kinetics
This involves more than one step the starting material is first converted to an unstable intermediate then goes on to form the product
Stepwise reaction
different kinds of reactions that do exist
- addition reaction
- elimination reaction
- substitution reaction
- rearrangement reaction
this if broken in addition reactions
pi bond
These are electrophiles because they contain an electron-deficient carbon
radicals and carbocations
This reaction occurs when two reactants exchange parts to give two new products
substitution reaction
equally divide electrons
homolysis or homolytic cleavage
It is unstable and can’t be isolated, but we can nevertheless imagine it to be an activated complex of the two reactants
transition state
It is formed in elimination reactions
pi bond
These reactions are exactly opposite
addition and elimination reactions
this represents the highest-energy structure involved in this step of the reaction
transition state
The nucleophile can be either?
negatively charged or neutral
bond making is?
exothermic
This is the overall description of how a reaction occur
reaction mechanism
This accounts for all reactants used and all products formed.
complete mechanism
the bigger the size of the halogen, the _____________ is the bond strength
lower
This reaction occurs when a single reactant splits into two products, often with formation of a small molecule such as water or HX .
elimination reaction
This indicates homolytic and homogenic steps forming radicals
“half” head (“fish-hook”)
is describes energy and equilibrium
thermodynamics
This indicates heterolytic and heterogenic steps forming ions
Complete head
Organic chemical reactions can be organized broadly in two ways:
WHAT kinds of reactions occur
HOW those reactions occur
This reaction is, in a sense, the opposite of addition reaction.
elimination reaction
For a reaction to take place, these must collide and reorganization of atoms and bonds must occur.
reaction molecules
Two ways of breaking or forming a bond:
- homolysis or homolytic cleavage
- heterolysis or heterolytic cleavage
The reactivity of organic molecules is influenced by two main factors:
- Electron-deficient sites
- Electron-rich site
it is the energy difference between reactants and transition state and determines how rapidly the reaction occurs at a given temperature
activation
The electrophile can be either?
positively charged or neutral
Atoms are rearranged resulting in the formation of a new substance or substances.
rearranged reaction
