Name: Score:
85 Multiple choice questions
Term 1 of 85
What is the RDS of the E1 mechanism?
The removal of the leaving group.
The molecule on which the substitution occurs
The polarized carbon-halogen bond
The chemical term for a one-step mechanism
,Term 2 of 85
Which type of substrates are unreactive in nucleophilic substitution reactions, and why?
- Aryl and vinyl halides
- substrates in which the halogen is attached to a carbon that is part of a
multiple bond.
These types of substrates have the halogen attached to a carbon with a
hybridization other than sp3 and prevent the nucleophile from reacting
with the substrate.
Aliphatic hydrocarbons (alkenes, alkanes, alkynes) that possess one or
more halogen atom substituents.
Since halogen atoms have the same bonding pattern as hydrogen atoms
(forming one single covalent bond), they often take the place of hydrogen
atoms in organic molecules.
X for a halogen atom
R for a carbon atom
tertiary (3°)
Term 3 of 85
What is the substrate in a nucleophilic substitution reaction?
The molecule on which the substitution occurs
Tertiary (3°)
The removal of the leaving group.
The replacing group.
A chemical species that seeks positive charge (nucleo = nucleus/positive charge, phile =
love).
,Term 4 of 85
As with substitution reactions, there are two major types of elimination mechanisms, designated
E1 and E2. What is their relationship with substitution reactions?
The molecule on which the substitution occurs
E1 competes with SN1; E2 competes with SN2.
Sn (Substitution, Nucleophilic)
When one or more hydrogens are attached to the carbon adjacent to (immediately next
to) the carbon bearing the leaving group.
Term 5 of 85
What are beta (β) carbons?
When strong bases are used as nucleophiles
Curved arrow notation is used to draw mechanisms in organic chemistry, just like when
showing electron resonance.
The molecule on which the substitution occurs
The carbon adjacent to the carbon bearing the halogen
Term 6 of 85
Aliphatic hydrocarbons
benzene rings
alkenes, alkynes, aromatics
alkanes, alkenes, alkynes
methane, butane, propane
, Term 7 of 85
While in substitution reactions, the halogen atom is replaced by another atom or group, in
general what happens in an elimination reaction?
Likely to have an SN2 and an E2 reaction (because there will be no protons to inhibit the
nucleophile).
Unlikely to have SN1 or E1
When one or more hydrogens are attached to the carbon adjacent to (immediately next
to) the carbon bearing the leaving group.
Elimination removes the halogen and a hydrogen atom from a carbon adjacent to the
carbon bearing the halogen to create an alkene.
The replacing group.
A chemical species that seeks positive charge (nucleo = nucleus/positive charge, phile =
love).
Term 8 of 85
What is the product of an elimination reaction of an alkyl halide substrate?
they rely on the nucleophile acting as a base to remove a proton instead of acting as a
nucleophile.
Larger nucleophiles are more efficient at backside attacks than small nucleophiles. Thus,
bisulfide (HS-) as a nucleophile would react faster than hydroxide (HO-) due to the larger
sulfur atom (with all other things being equal).
The solution in which the reagents are combined.
The product of an elimination reaction is an alkene.
Elimination reactions of alkyl halide substrates are useful synthetically, as they provide a
route for functional group interconversion of halides to alkenes.
85 Multiple choice questions
Term 1 of 85
What is the RDS of the E1 mechanism?
The removal of the leaving group.
The molecule on which the substitution occurs
The polarized carbon-halogen bond
The chemical term for a one-step mechanism
,Term 2 of 85
Which type of substrates are unreactive in nucleophilic substitution reactions, and why?
- Aryl and vinyl halides
- substrates in which the halogen is attached to a carbon that is part of a
multiple bond.
These types of substrates have the halogen attached to a carbon with a
hybridization other than sp3 and prevent the nucleophile from reacting
with the substrate.
Aliphatic hydrocarbons (alkenes, alkanes, alkynes) that possess one or
more halogen atom substituents.
Since halogen atoms have the same bonding pattern as hydrogen atoms
(forming one single covalent bond), they often take the place of hydrogen
atoms in organic molecules.
X for a halogen atom
R for a carbon atom
tertiary (3°)
Term 3 of 85
What is the substrate in a nucleophilic substitution reaction?
The molecule on which the substitution occurs
Tertiary (3°)
The removal of the leaving group.
The replacing group.
A chemical species that seeks positive charge (nucleo = nucleus/positive charge, phile =
love).
,Term 4 of 85
As with substitution reactions, there are two major types of elimination mechanisms, designated
E1 and E2. What is their relationship with substitution reactions?
The molecule on which the substitution occurs
E1 competes with SN1; E2 competes with SN2.
Sn (Substitution, Nucleophilic)
When one or more hydrogens are attached to the carbon adjacent to (immediately next
to) the carbon bearing the leaving group.
Term 5 of 85
What are beta (β) carbons?
When strong bases are used as nucleophiles
Curved arrow notation is used to draw mechanisms in organic chemistry, just like when
showing electron resonance.
The molecule on which the substitution occurs
The carbon adjacent to the carbon bearing the halogen
Term 6 of 85
Aliphatic hydrocarbons
benzene rings
alkenes, alkynes, aromatics
alkanes, alkenes, alkynes
methane, butane, propane
, Term 7 of 85
While in substitution reactions, the halogen atom is replaced by another atom or group, in
general what happens in an elimination reaction?
Likely to have an SN2 and an E2 reaction (because there will be no protons to inhibit the
nucleophile).
Unlikely to have SN1 or E1
When one or more hydrogens are attached to the carbon adjacent to (immediately next
to) the carbon bearing the leaving group.
Elimination removes the halogen and a hydrogen atom from a carbon adjacent to the
carbon bearing the halogen to create an alkene.
The replacing group.
A chemical species that seeks positive charge (nucleo = nucleus/positive charge, phile =
love).
Term 8 of 85
What is the product of an elimination reaction of an alkyl halide substrate?
they rely on the nucleophile acting as a base to remove a proton instead of acting as a
nucleophile.
Larger nucleophiles are more efficient at backside attacks than small nucleophiles. Thus,
bisulfide (HS-) as a nucleophile would react faster than hydroxide (HO-) due to the larger
sulfur atom (with all other things being equal).
The solution in which the reagents are combined.
The product of an elimination reaction is an alkene.
Elimination reactions of alkyl halide substrates are useful synthetically, as they provide a
route for functional group interconversion of halides to alkenes.
