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Ch.11:RxnsofAlkylHalides:N'philicSubstitutions&Eliminations
Part of OCHEM Test 4
364
Organic Chemistry
Undergraduate 2
07/14/2017

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Term
the types of substitution rxns
Definition
SN1 and SN2
Term
in SN2 rxns, ______ rxns of primary and secondary alkyl halides always proceed with inversion of configuration
Definition
nucleophilic substitution rxns
Term
in SN2 rxns, nucleophilic substitution rxns of ______ always proceed with inversion of configuration
Definition
primary and secondary alkyl halides
Term
in SN2 rxns, nucleophilic substitution rxns of primary and secondary alkyl halides always proceed with ______
Definition
inversion of configuration
Term
the kinetics of a rxn measure the relationship between ______ and the rate of rxn
Definition
reactant concentrations and product concentrations
Term
the kinetics of a rxn measure the relationship between reactant concentrations and product concentrations and ______
Definition
the rate of rxn
Term
in a(n) ______, rxn rate depends on the concentration of both alkyl halide and nucleophile (bimolecular rxn).
Definition
SN2 rxn
Term
in an SN2 rxn, ______ depends on the concentration of both alkyl halide and nucleophile (bimolecular rxn).
Definition
rxn rate
Term
in an SN2 rxn, rxn rate depends on the ______ of both alkyl halide and nucleophile (bimolecular rxn).
Definition
concentration
Term
in an SN2 rxn, rxn rate depends on the concentration of ______.
Definition
both alkyl halide and nucleophile (bimolecular rxn)
Term
the type of rxn an SN2 rxn is
Definition
2nd order
Term
rate law for a 2nd order rxn
Definition
rate = k[RX][Nu]
Term
the mechanism of an SN2 rxn
Definition
takes place in a single step, w/o intermediates
Term
In a(n) ______ rxn, the nucleophile attacks the substrate from a direction directly opposite to the leaving group.
Definition
2nd order rxn
Term
In a 2nd order rxn, the ______ attacks the substrate from a direction directly opposite to the leaving group.
Definition
nucleophile
Term
In a 2nd order rxn, the nucleophile attacks the ______ from a direction directly opposite to the leaving group.
Definition
substrate
Term
In a 2nd order rxn, the nucleophile attacks the substrate from a direction ______ to the leaving group.
Definition
directly opposite
Term
In a 2nd order rxn, the nucleophile attacks the substrate from a direction directly opposite to the ______.
Definition
leaving group
Term
why there's inversion of configuration in SN2 rxns
Definition
because the nucleophile attacks the substrate from a direction directly opposite to the leaving group
Term
what happens in the transition state of an SN2 rxn?
Definition
the new bond forms at the same time the old bond breaks
Term
In an SN2 rxn, ______ charge is shared between the attacking nucleophile and the leaving group.
Definition
negative
Term
In an SN2 rxn, negative charge is shared between the ______ and the leaving group.
Definition
attacking nucleophile
Term
In an SN2 rxn, negative charge is shared between the attacking nucleophile and the ______.
Definition
leaving group
Term
in the transition state of an SN2 rxn, the 3 remaining bonds to C are in a(n) ______ arrangement.
Definition
planar
Term
In a(n) ______ rxn both substrate and nucleophile are involved in the step whose rate is measured.
Definition
SN2 rxn
Term
In an SN2 rxn both ______ and ______ are involved in the step whose rate is measured.
Definition
substrate
nucleophile
Term
In an SN2 rxn both substrate and nucleophile are involved in ______.
Definition
the step whose rate is measured
Term
the things that affect the rate of an SN2 rxn
Definition
changes in the energy levels of the reactants or of the transition state
Term
the rate of an SN2 rxn is decreased if the ______ is bulky
Definition
substrate
Term
the rate of an SN2 rxn is decreased if the substrate is ______
Definition
bulky
Term
substrates in order of increasing reactivity in SN2 rxns
Definition
tertiary, neopentyl, secondary, primary, methyl
Term
SN2 rxns can occur only at...
Definition
relatively unhindered sites
Term
______ halides are unreactive to SN2 substitutions.
Definition
Vinylic and aryl
Term
Vinylic and aryl halides are ______ to SN2 substitutions.
Definition
unreactive
Term
Vinylic and aryl halides are unreactive to ______.
Definition
SN2 substitutions
Term
any species can act as a nucleophile if...
Definition
it has an unshared electron pair
Term
if the nucleophile has a ______ charge, tyhe product is neutral
Definition
negative
Term
if the nucleophile has a negative charge, tyhe product is ______
Definition
neutral
Term
if the nucleophile is ______, the product is positive
Definition
neutral
Term
if the nucleophile is neutral, the product is ______
Definition
positive
Term
the reactivity of a nucleophile is dependent on...
Definition
rxn conditions
Term
in general, ______ parallels basicity
Definition
nucleophilicity
Term
in general, nucleophilicity parallels ______
Definition
basicity
Term
periodic trend in nucleophilicity
Definition
South

(increases as you go down a column)
Term
negatively charged nucleophiles are usually (more or less) reactive than neutral nucleophiles
Definition
more
Term
______ nucleophiles are usually more reactive than neutral nucleophiles
Definition
negatively charged
Term
negatively charged nucleophiles are usually more reactive than ______ nucleophiles
Definition
neutral
Term
in general, the best leaving groups are...
Definition
those that best stabilize negative charge
Term
usually, the best leaving groups in SN2 rxns are...
Definition
the weakest bases
Term
good leaving groups in SN2 rxns ______ the energy of the transition state
Definition
lower
Term
good leaving groups in SN1 rxns lower the energy of ______
Definition
the transition state
Term
poor leaving groups in SN2 rxns include...
Definition
-F- -HO- -RO- -H2N-
Term
poor leaving groups (can or can not) be converted to better leaving groups
Definition
can
Term
______ slow SN2 rxns by lowering the reactivity of the nucleophile
Definition
polar, protic solvents
Term
polar, protic solvents ______ SN2 rxns by lowering the reactivity of the nucleophile
Definition
slow
Term
polar, protic solvents slow SN2 rxns by ______ the reactivity of the nucleophile
Definition
lowering
Term
polar, protic solvents slow SN2 rxns by lowering ______ of the nucleophile
Definition
the reactivity
Term
polar, protic solvents slow SN2 rxns by lowering the reactivity of ______
Definition
the nucleophile
Term
polar, protic solvents slow SN2 rxns by...
Definition
lowering the reactivity of the nucleophile
Term
______ raise the ground-state energy of the nucleophile and make it more reactive
Definition
polar, aprotic solvents
Term
polar, aprotic solvents ______ the ground-state energy of the nucleophile and make it more reactive
Definition
raise
Term
polar, aprotic solvents raise the ______ of the nucleophile and make it more reactive
Definition
ground-state energy
Term
polar, aprotic solvents raise the ground-state energy of the ______ and make it more reactive
Definition
nucleophile
Term
polar, aprotic solvents raise the ground-state energy of the nucleophile and make it more ______
Definition
reactive
Term
In SN2 rxns, ______ of the substrate raises the energy of the transition state, increasing ΔG, and decreasing the rxn rate.
Definition
steric hindrance
Term
In SN2 rxns, steric hindrance of the ______ raises the energy of the transition state, increasing ΔG, and decreasing the rxn rate.
Definition
substrate
Term
In SN2 rxns, steric hindrance of the substrate ______ the energy of the transition state, ______ ΔG, and ______ the rxn rate.
Definition
raises
increasing
decreasing
Term
In SN2 rxns, steric hindrance of the substrate raises the ______, increasing ______, and decreasing the ______.
Definition
energy of the transition state ΔG rxn rate
Term
(more or less) reactive nucleophiles have a higher ground-state energy, decreasing ΔG, and increasing the rxn rate
Definition
more
Term
more reactive nucleophiles have a (higher or lower) ground-state energy, decreasing ΔG, and increasing the rxn rate
Definition
higher
Term
more reactive nucleophiles have a higher ______, decreasing ΔG, and increasing the rxn rate
Definition
ground-state energy
Term
more reactive nucleophiles have a higher ground-state energy, ______ ΔG, and ______ the rxn rate
Definition
decreasing
increasing
Term
more reactive nucleophiles have a higher ground-state energy, decreasing ______, and increasing the ______
Definition
ΔG rxn rate
Term
(good or bad) leaving groups decrease the energy of the transition state, decreasing ΔG, and increasing the rxn rate
Definition
good
Term
good leaving groups ______ the energy of the transition state, ______ ΔG, and ______ the rxn rate
Definition
decrease
decreasing
increasing
Term
good leaving groups decrease the energy of the ______, decreasing ______, and increasing the ______
Definition
transition state ΔG rxn rate
Term
______ solvents solvate the nucleophile, lowering the ground-state energy, increasing ΔG, and decreasing the rxn rate
Definition
polar protic
Term
polar protic solvents (solvate or don't solvate) the nucleophile, lowering the ground-state energy, increasing ΔG, and decreasing the rxn rate
Definition
solvate
Term
polar protic solvents solvate the ______, lowering the ground-state energy, increasing ΔG, and decreasing the rxn rate
Definition
nucleophile
Term
polar protic solvents solvate the nucleophile, ______ the ground-state energy, ______ ΔG, and ______ the rxn rate
Definition
lowering
increasing
decreasing
Term
polar protic solvents solvate the nucleophile, lowering the ______, increasing ______, and decreasing the ______
Definition
ground-state energy ΔG rxn rate
Term
______ solvents don't solvate the nucleophile, raising the ground-state energy, decreasing ΔG, and increasing the rxn rate
Definition
polar aprotic
Term
polar aprotic solvents (solvate or don't solvate) the nucleophile, raising the ground-state energy, decreasing ΔG, and increasing the rxn rate
Definition
don't solvate
Term
polar aprotic solvents don't solvate the ______, raising the ground-state energy, decreasing ΔG, and increasing the rxn rate
Definition
nucleophile
Term
polar aprotic solvents don't solvate the nucleophile, ______ the ground-state energy, ______ ΔG, and ______ the rxn rate
Definition
raising
decreasing
increasing
Term
polar aprotic solvents don't solvate the nucleophile, raising the ______, decreasing ______, and increasing the ______
Definition
ground-state energy ΔG rxn rate
Term
substitution rxns in which tertiary halides are the least reactive
Definition
SN2 rxns
Term
substitution rxns in which tertiary halides are the most reactive
Definition
SN1 rxns
Term
kinetics of an SN1 rxn
Definition
the rate of rxn of a tertiary alkyl halide with water depends only on the concentration of the alkyl halide (unimolecular rxn)
Term
in an SN1 rxn, the ______ of a tertiary alkyl halide with water depends only on the concentration of the alkyl halide (unimolecular rxn)
Definition
rate of rxn
Term
in an SN1 rxn, the rate of rxn of ______ with water depends only on the concentration of the alkyl halide (unimolecular rxn)
Definition
a tertiary alkyl halide
Term
in an SN1 rxn, the rate of rxn of a tertiary alkyl halide with ______ depends only on the concentration of the alkyl halide (unimolecular rxn)
Definition
water
Term
in an SN1 rxn, the rate of rxn of a tertiary alkyl halide with water depends only on ______ (unimolecular rxn)
Definition
the concentration of the alkyl halide
Term
in an SN1 rxn, the rate of rxn of a tertiary alkyl halide with water depends only on the concentration of the alkyl halide (______)
Definition
unimolecular rxn
Term
the type of rxn an SN1 rxn is
Definition
first order
Term
rxn rate of an SN1 rxn
Definition
rate = k[RX]
Term
in an SN1 rxn, only ______ is involved in the slowest, or rate limiting, step, and the nucleophile is involved in a different, faster step
Definition
RX
Term
in an SN1 rxn, only RX is involved in ______, step, and the nucleophile is involved in a different, faster step
Definition
the slowest, or rate limiting
Term
in an SN1 rxn, only RX is involved in the slowest, or rate limiting, step, and the ______ is involved in a different, faster step
Definition
nucleophile
Term
in an SN1 rxn, only RX is involved in the slowest, or rate limiting, step, and the nucleophile is involved in ______ step
Definition
a different, faster
Term
the number of steps in an SN1 rxn
Definition
at least 2
Term
how an SN1 rxn occurs
Definition
slow dissociation of the substrate followed by rapid rxn with the nucleophile
Term
in ______, slow dissociation of the substrate is followed by rapid rxn with the nucleophile
Definition
an SN1 rxn
Term
in an SN1 rxn, ______ is followed by rapid rxn with the nucleophile
Definition
slow dissociation of the substrate
Term
in an SN1 rxn, slow dissociation of the substrate is followed by ______
Definition
rapid rxn with the nucleophile
Term
an SN1 rxn of an enantiomer produces...
Definition
a racemic product
Term
why an SN1 rxn of an enantiomer produces a racemic product
Definition
because it proceeds thru a planar, achiral intermediate
Term
the intermediate of an SN1 rxn of an enantiomer
Definition
a planar, achiral intermediate
Term
do SN1 rxns proceed with complete racemization?
Definition
few do
Term
why few SN1 rxns proceed with complete racemization
Definition
because the ion pair formed by the leaving group and the carbocation sometimes shields one side of the carbocation from attack before the leaving group can diffuse away
Term
factors that lower ______ favor faster rxns
Definition
ΔG
Term
factors that lower ΔG favor ______
Definition
faster rxns
Term
the (more or less) stable the carbocation intermediate, the faster the SN1 rxn
Definition
more
Term
the more stable the carbocation intermediate, the (faster or slower) the SN1 rxn
Definition
faster
Term
substrates in order of increasing reactivity in SN1 rxn
Definition
methyl, primary, secondary and allyl and benzyl, tertiary
Term
______ and ______ substrates are also reactive in SN2 rxns
Definition
allylic
benzylic
Term
allylic and benzylic substrates are also reactive in ______
Definition
SN2 rxns
Term
the best leaving groups in SN1 rxns
Definition
the conjugate bases of strong acids
Term
can water act as a leaving group in SN1 rxns?
Definition
yes
Term
the effect of changes in the nucleophile on SN1 rxnspolar solvents stabilize the carbocation intermediate and increase the rxn rate
Definition
no effect
Term
______ (high dielectric constant) increase the rates of SN1 rxns
Definition
polar solvents
Term
polar solvents (______) increase the rates of SN1 rxns
Definition
high dielectric constant
Term
polar solvents (high dielectric constant) (increase or decrease) the rates of SN1 rxns
Definition
increase
Term
polar solvents (high dielectric constant) increase the rates of ______
Definition
SN1 rxns
Term
in SN1 rxns, ______ stabilize the carbocation intermediate more than the reactants and lower ΔG
Definition
polar solvents
Term
in SN1 rxns, polar solvents ______ the carbocation intermediate more than the reactants and lower ΔG
Definition
stabilize
Term
in SN1 rxns, polar solvents stabilize the ______ more than the ______ and lower ΔG
Definition
carbocation intermediate
reactants
Term
in SN1 rxns, polar solvents stabilize the carbocation intermediate (more or less) than the reactants and lower ΔG
Definition
more
Term
in SN1 rxns, polar solvents stabilize the carbocation intermediate more than the reactants and ______ ΔG
Definition
lower
Term
in SN1 rxns, polar solvents stabilize the carbocation intermediate more than the reactants and lower ______
Definition
ΔG
Term
______ stabilize by orienting themselves around the carbocation, with electron-rich ends facing the positive charge
Definition
polar solvents
Term
polar solvents stabilize by ______, with electron-rich ends facing the positive charge
Definition
orienting themselves around the carbocation
Term
polar solvents stabilize by orienting themselves around the carbocation, with ______ facing the positive charge
Definition
electron-rich ends
Term
polar solvents stabilize by orienting themselves around the carbocation, with electron-rich ends facing ______
Definition
the positive charge
Term
the best substrates in SN1 rxns
Definition
those that form the most stable carbocations
Term
good leaving groups in SN1 rxns ______ the energy of the transition state leading to carbocation formation and increase the rxn rate
Definition
lower
Term
good leaving groups in SN1 rxns lower the energy of ______ leading to carbocation formation and increase the rxn rate
Definition
the transition state
Term
good leaving groups in SN1 rxns lower the energy of the transition state leading to ______ and increase the rxn rate
Definition
carbocation formation
Term
good leaving groups in SN1 rxns lower the energy of the transition state leading to carbocation formation and ______ the rxn rate
Definition
increase
Term
good leaving groups in SN1 rxns lower the energy of the transition state leading to carbocation formation and increase the ______
Definition
rxn rate
Term
in SN1 rxns, the ______ doesn't affect the rxn rate, but it must be nonbasic
Definition
nucleophile
Term
in SN1 rxns, the nucleophile (does or doesn't) affect the rxn rate, but it must be nonbasic
Definition
doesn't
Term
in SN1 rxns, the nucleophile doesn't affect the ______, but it must be nonbasic
Definition
rxn rate
Term
in SN1 rxns, the nucleophile doesn't affect the rxn rate, but it must be ______
Definition
nonbasic
Term
in SN1 rxns, ______ solvents stabilize the carbocation intermediate and increase the rxn rate
Definition
polar
Term
in SN1 rxns, polar solvents ______ the carbocation intermediate and increase the rxn rate
Definition
stabilize
Term
in SN1 rxns, polar solvents stabilize the ______ and increase the rxn rate
Definition
carbocation intermediate
Term
in SN1 rxns, polar solvents stabilize the carbocation intermediate and ______ the rxn rate
Definition
increase
Term
in SN1 rxns, polar solvents stabilize the carbocation intermediate and increase the ______
Definition
rxn rate
Term
both SN1 and SN2 rxns occur often in...
Definition
biochemical pathways
Term
in SN1 rxns, the leaving group is often...
Definition
an organodiphosphate
Term
SN2 rxns are involved in...
Definition
biological methylations
Term
a(n) (acidic or basic) nucleophile can cause elimination of HX from an alkyl halide to form a C=C 2bl bond
Definition
basic
Term
a basic ______ can cause elimination of HX from an alkyl halide to form a C=C 2bl bond
Definition
nucleophile
Term
a basic nucleophile can cause ______ of HX from an alkyl halide to form a C=C 2bl bond
Definition
elimination
Term
a basic nucleophile can cause elimination of ______ from an alkyl halide to form a C=C 2bl bond
Definition
HX
Term
a basic nucleophile can cause elimination of HX from ______ to form a C=C 2bl bond
Definition
an alkyl halide
Term
a basic nucleophile can cause elimination of HX from an alkyl halide to form ______
Definition
a C=C 2bl bond
Term
the major product of elimination of HX from an alkyl halide
Definition
the product with the more substituted 2bl bond
Term
the basis of Zaitsev's rule
Definition
the major product of elimination of HX from an alkyl halide is the product with the more substituted 2bl bond
Term
some types of rxns of elimination of HX from an alkyl halide
Definition
-E2
-E1
-E1cB
Term
a(n) ______ rxn occurs when an alkyl halide is treated with a strong base
Definition
E2
Term
an E2 rxn occurs when ______ is treated with a strong base
Definition
an alkyl halide
Term
an E2 rxn occurs when a alkyl halide is treated with ______
Definition
a strong base
Term
how an E2 rxn occurs
Definition
in 1 step, w/o intermediates
Term
the kinetics of E2 rxns
Definition
2nd order
Term
an effect shown by E2 rxns
Definition
the deuterium isotope effect
Term
the deuterium isotope effect in E2 rxns
Definition
in a rxn in which the C-H bond is cleaved in the rate-limiting step, substitution of -D for -H results in a decrease in rate
Term
in the deuterium isotope effect in E2 rxns, when the ______ is cleaved in the rate-limiting step, substitution of -D for -H results in a decrease in rate
Definition
C-H bond
Term
in the deuterium isotope effect in E2 rxns, when the C-H bond is ______ in the rate-limiting step, substitution of -D for -H results in a decrease in rate
Definition
cleaved
Term
in the deuterium isotope effect in E2 rxns, when the C-H bond is cleaved in ______, substitution of -D for -H results in a decrease in rate
Definition
the rate-limiting step
Term
in the deuterium isotope effect in E2 rxns, when the C-H bond is cleaved in the rate-limiting step, ______ of -D for -H results in a decrease in rate
Definition
substitution
Term
in the deuterium isotope effect in E2 rxns, when the C-H bond is cleaved in the rate-limiting step, substitution of ______ for ______ results in a decrease in rate
Definition
-D
-H
Term
in the deuterium isotope effect in E2 rxns, when the C-H bond is cleaved in the rate-limiting step, substitution of -D for -H results in ______
Definition
a decrease in rate
Term
______ rxns involve C-H bond breaking in the rate-limiting step
Definition
E2
Term
E2 rxns involve ______ in the rate-limiting step
Definition
C-H bond breaking
Term
E2 rxns involve C-H bond breaking in the ______
Definition
rate-limiting step
Term
E2 rxns always occur with ______ geometry
Definition
periplanar
Term
______ geometry is required for E2 rxns because of the need for overlap of the sp3 orbitals of the reactant as they become π orbitals in the product
Definition
periplanar
Term
periplanar geometry is required for E2 rxns because of the need for ______ of the sp3 orbitals of the reactant as they become π orbitals in the product
Definition
overlap
Term
periplanar geometry is required for E2 rxns because of the need for overlap of the ______ orbitals of the reactant as they become ______ orbitals in the product
Definition
sp3 π
Term
periplanar geometry is required for E2 rxns because of the need for overlap of the sp3 orbitals of the ______ as they become π orbitals in the ______
Definition
reactant
product
Term
______ geometry is preferred in E2 rxns because it allows the substituents of the 2 C's to assume a staggered relationship
Definition
anti periplanar
Term
anti periplanar geometry is preferred in E2 rxns because it allows ______ of the 2 C's to assume a staggered relationship
Definition
the substituents
Term
anti periplanar geometry is preferred in E2 rxns because it allows the substituents of the 2 C's to assume ______
Definition
a staggered relationship
Term
______ geometry occurs in E2 rxns only when anti periplanar geometry isn't possible
Definition
syn periplanar
Term
syn periplanar geometry occurs in E2 rxns only when ______
Definition
anti periplanar geometry isn't possible
Term
the preference for ______ geometry in E2 rxns results in the formation of 2bl bonds with specific E, Z configurations
Definition
anti periplanar
Term
the preference for anti periplanar geometry in E2 rxns results in the formation of ______ with specific E, Z configurations
Definition
2bl bonds
Term
the preference for anti periplanar geometry in E2 rxns results in the formation of 2bl bonds with specific ______
Definition
E, Z configurations
Term
the chemistry of substituted cyclohexanes is controlled by...
Definition
their conformations
Term
the preference for ______ geometry for E2 relations can be met only if the atoms to be eliminated have a trans-diaxial relationship
Definition
anti periplanar
Term
the preference for anti periplanar geometry for ______ can be met only if the atoms to be eliminated have a trans-diaxial relationship
Definition
E2 relations
Term
the preference for anti periplanar geometry for E2 relations can be met only if ______ have a trans-diaxial relationship
Definition
the atoms to be eliminated
Term
the preference for anti periplanar geometry for E2 relations can be met only if the atoms to be eliminated have ______
Definition
a trans-diaxial relationship
Term
______ occurs when the intermediate carbocation of an SN1 loses H+ to form a C=C bond
Definition
an E1 rxn
Term
an E1 rxn occurs when ______ of an SN1 loses H+ to form a C=C bond
Definition
the intermediate carbocation
Term
an E1 rxn occurs when the intermediate carbocation of ______ loses H+ to form a C=C bond
Definition
an SN1
Term
an E1 rxn occurs when the intermediate carbocation of an SN1 ______ to form a C=C bond
Definition
loses H+
Term
an E1 rxn occurs when the intermediate carbocation of an SN1 loses H+ to form ______
Definition
a C=C bond
Term
______ usually occur in competition with SN1 rxns
Definition
E1 rxns
Term
E1 rxns usually occur ______ with SN1 rxns
Definition
in competition
Term
E1 rxns usually occur in competition with ______
Definition
SN1 rxns
Term
the kinetics of E1 rxns
Definition
1st order
Term
the geometric requirement for the groups to be eliminated in an E1 rxn
Definition
no geometric requirement
Term
the product of the E1 rxn
Definition
the most stable (Zaitsev) product
Term
what the cB stands for in E1cB
Definition
conjugate base
Term
how the E1cB rxn takes place
Definition
the E1cB rxn takes place thru a carbocation intermediate
Term
______ of an E1cB rxn involves base-induced abstraction of a proton
Definition
the rate-limiting step
Term
the rate-limiting step of ______ rxn involves base-induced abstraction of a proton
Definition
an E1cB
Term
the rate-limiting step of an E1cB rxn involves ______
Definition
base-induced abstraction of a proton
Term
the ______ in E1cB rxns is often poor
Definition
leaving group
Term
the leaving group in ______ is often poor
Definition
E1cB rxns
Term
the leaving group in E1cB rxns is often ______
Definition
poor
Term
in ______, a carbonyl group stabilizes the anion
Definition
E1cB rxns
Term
in E1cB rxns, ______ stabilizes the anion
Definition
a carbonyl group
Term
in E1cB rxns, a carbonyl group ______ the anion
Definition
stabilizes
Term
in E1cB rxns, a carbonyl group stabilizes ______
Definition
the anion
Term
the E1cB is fairly common in...
Definition
biochemical pathways
Term
in rxns with ______ halides, SN2 rxns are usually observed
Definition
primary
Term
in rxns with primary halides, ______ rxns are usually observed
Definition
SN2
Term
in rxns with ______ halides, E1 rxns occur if a strong, bulky base is used
Definition
primary
Term
in rxns with primary halides, ______ rxns occur if a strong, bulky base is used
Definition
E1
Term
in rxns with primary halides, E1 rxns occur if ______ base is used
Definition
a strong, bulky
Term
in rxns with primary halides, E1 rxns occur if a strong, bulky (acid or base) is used
Definition
base
Term
in rxns with ______ halides, E1cB rxns occur if the leaving group is 2 C's away from a carbonyl group
Definition
primary
Term
in rxns with primary halides, ______ rxns occur if the leaving group is 2 C's away from a carbonyl group
Definition
E1cB
Term
in rxns with primary halides, E1cB rxns occur if the ______ is 2 C's away from a carbonyl group
Definition
leaving group
Term
in rxns with primary halides, E1cB rxns occur if the leaving group is ______ from a carbonyl group
Definition
2 C's away
Term
in rxns with primary halides, E1cB rxns occur if the leaving group is 2 C's away from ______
Definition
a carbonyl group
Term
in rxns with ______ halides, SN2 and E2 rxns occur in competition
Definition
secondary
Term
in rxns with secondary halides, ______ and ______ rxns occur in competition
Definition
SN2 E2
Term
in rxns with secondary halides, SN2 and E2 rxns occur ______
Definition
in competition
Term
in rxns with ______ halides, strong bases promote E2 elimination
Definition
secondary
Term
in rxns with secondary halides, ______ promote E2 elimination
Definition
strong bases
Term
in rxns with secondary halides, strong bases ______ E2 elimination
Definition
promote
Term
in rxns with secondary halides, strong bases promote ______
Definition
E2 elimination
Term
______ halides, especially allylic and benzylic halides, can react by SN1 and E1 routes if weakly basic nucleophiles and protic solvents are used
Definition
secondary
Term
secondary halides, especially secondary______ halides, can react by SN1 and E1 routes if weakly basic nucleophiles and protic solvents are used
Definition
secondary
Term
secondary halides, especially allylic and benzylic halides, can react by ______ routes if weakly basic nucleophiles and protic solvents are used
Definition
SN1 and E1
Term
secondary halides, especially allylic and benzylic halides, can react by SN1 and E1 routes if ______ are used
Definition
weakly basic nucleophiles and protic solvents
Term
in rxns with ______ halides, E1cB rxn occurs if the leaving group is 2 C's away from a carbonyl group
Definition
secondary
Term
in rxns with secondary halides, ______ rxn occurs if the leaving group is 2 C's away from a carbonyl group
Definition
E1cB
Term
in rxns with secondary halides, E1cB rxn occurs if ______ is 2 C's away from a carbonyl group
Definition
the leaving group
Term
in rxns with secondary halides, E1cB rxn occurs if the leaving group is ______ from a carbonyl group
Definition
2 C's away
Term
in rxns with secondary halides, E1cB rxn occurs if the leaving group is 2 C's away from ______
Definition
a carbonyl group
Term
under (acidic or basic) conditions, E2 elimination is favored in rxns with tertiary halides
Definition
basic
Term
under basic conditions, ______ elimination is favored in rxns with tertiary halides
Definition
E2
Term
under basic conditions, E2 ______ is favored in rxns with tertiary halides
Definition
elimination
Term
under basic conditions, E2 elimination is favored in rxns with ______ halides
Definition
tertiary
Term
in rxns with ______ halides, SN1 and E1 products are formed under nonbasic conditions
Definition
tertiary
Term
in rxns with tertiary halides, ______ are formed under nonbasic conditions
Definition
SN1 and E1 products
Term
in rxns with tertiary halides, SN1 and E1 products are formed under ______ conditions
Definition
nonbasic
Term
in rxns with ______ halides, E1cB rxns occur if the leaving group is 2 C's away
Definition
tertiary
Term
in rxns with tertiary halides, ______ rxns occur if the leaving group is 2 C's away
Definition
E1cB
Term
in rxns with tertiary halides, E1cB rxns occur if ______ is 2 C's away
Definition
the leaving group
Term
in rxns with tertiary halides, E1cB rxns occur if the leaving group is ______
Definition
2 C's away
Term
the important functions of the leaving group in substitution rxns
Definition
1: withdraws electron density from the C atom from which it is attached
2: is capable of stabilizing the negative charge after being expelled
Term
the meaning of the 2 in SN2
Definition
it is a 2nd order rxn, in which the rxn depends on the concentrations of both the nucleophile and the electrophile
Term
the major difference between SN1 and SN2 rxns
Definition
only SN1 rxns have a carbocation intermediate between the LG leaving and the nucleophile arriving
Term
depiction of an SN1 rxn
Definition
[image]
Term
depiction of an SN2 rxn
Definition
[image]
Term
rxn coordinate diagram for SN1 rxn
Definition
[image]
Term
the meaning of the 1 in SN1
Definition
the rate is 1st order due to the rate of it being dependent on the concentration of only the LG (electrophile)
Term
in substitution and elimination rxns, the electrophile is also called the...
Definition
substrate
Term
the type of substrate ideal for SN2 rxns
Definition
primary
Term
[image]
Definition
depiction of an SN1 rxn
Term
[image]
Definition
depiction of an SN2 rxn
Term
[image]
Definition
rxn coordinate diagram for SN1 rxn
Term
the first step in SN1 rxns
Definition
loss of the leaving group to form the carbocation
Term
the paramount issue in SN1 rxns
Definition
the stability of the carbocation
Term
effect of strong nucleophile on SN2 rxn
Definition
speeds it up
Term
effect of weak nucleophile on SN2 rxn
Definition
slows it down
Term
effect of strength of nucleophile on SN1 rxn
Definition
no effect
Term
why strength of nucleophile has no effect on rate of SN1 rxn
Definition
because the rate of it is dependent only on the concentration of the substrate, not the nucleophile
Term
some strong nucleophiles
Definition
-I- -HS- -HO- -Br- -H2S -RO- -Cl- -RSH -NC-
Term
some weak nucleophiles
Definition
-F- -H2O -ROH
Term
in general, good leaving groups are...
Definition
the conjugate bases of strong acids
Term
how a bad leaving group can be converted into a good leaving group
Definition
treating it with a strong acid, thus protonating it
Term
the most commonly used leaving groups
Definition
halides and sulfonate ions
Term
what makes one leaving group better than the other?
Definition
being a weaker base (more stable)
Term
protic solvent
Definition
solvent that has a proton connected to an electronegative atom

called protic because the solvent can serve as a source of protons
Term
aprotic solvent
Definition
solvent that does not have a proton on an electronegative atom
Term
the type of solvent that will best catalyze a SN2 rxn
Definition
polar aprotic
Term
why polar aprotic solvents are better for SN2 rxns than polar protic solvents
Definition
because polar protic solvents surround the nucleophile in a solvent shell, but polar aprotic solvents don't
Term
the important functions of the leaving group in substitution rxns
Definition
1: withdraws electron density from the C atom from which it is attached
2: is capable of stabilizing the negative charge after being expelled
Term
the meaning of the 2 in SN2
Definition
it is a 2nd order rxn, in which the rxn depends on the concentrations of both the nucleophile and the electrophile
Term
the major difference between SN1 and SN2 rxns
Definition
only SN1 rxns have a carbocation intermediate between the LG leaving and the nucleophile arriving
Term
depiction of an SN1 rxn
Definition
[image]
Term
depiction of an SN2 rxn
Definition
[image]
Term
rxn coordinate diagram for SN1 rxn
Definition
[image]
Term
the meaning of the 1 in SN1
Definition
the rate is 1st order due to the rate of it being dependent on the concentration of only the LG (electrophile)
Term
in substitution and elimination rxns, the electrophile is also called the...
Definition
substrate
Term
the type of substrate ideal for SN2 rxns
Definition
primary
Term
[image]
Definition
depiction of an SN1 rxn
Term
[image]
Definition
depiction of an SN2 rxn
Term
[image]
Definition
rxn coordinate diagram for SN1 rxn
Term
the first step in SN1 rxns
Definition
loss of the leaving group to form the carbocation
Term
the paramount issue in SN1 rxns
Definition
the stability of the carbocation
Term
effect of strong nucleophile on SN2 rxn
Definition
speeds it up
Term
effect of weak nucleophile on SN2 rxn
Definition
slows it down
Term
effect of strength of nucleophile on SN1 rxn
Definition
no effect
Term
why strength of nucleophile has no effect on rate of SN1 rxn
Definition
because the rate of it is dependent only on the concentration of the substrate, not the nucleophile
Term
some strong nucleophiles
Definition
-I- -HS- -HO- -Br- -H2S -RO- -Cl- -RSH -NC-
Term
some weak nucleophiles
Definition
-F- -H2O -ROH
Term
in general, good leaving groups are...
Definition
the conjugate bases of strong acids
Term
how a bad leaving group can be converted into a good leaving group
Definition
treating it with a strong acid, thus protonating it
Term
the most commonly used leaving groups
Definition
halides and sulfonate ions
Term
what makes one leaving group better than the other?
Definition
being a weaker base (more stable)
Term
protic solvent
Definition
solvent that has a proton connected to an electronegative atom

called protic because the solvent can serve as a source of protons
Term
aprotic solvent
Definition
solvent that does not have a proton on an electronegative atom
Term
the type of solvent that will best catalyze a SN2 rxn
Definition
polar aprotic
Term
why polar aprotic solvents are better for SN2 rxns than polar protic solvents
Definition
because polar protic solvents surround the nucleophile in a solvent shell, but polar aprotic solvents don't
Term
the meaning of the 2 in E2
Definition
the 2 means bimolecular
Term
the function of the reagent in a substitution rxn
Definition
nucleophile, which attacks electrophilic position
Term
function of the reagent in an elimination rxn
Definition
base, which removes proton
Term
Zaitsev product
Definition
the more substituted alkene that results from an E2 rxn
Term
Hofmann product
Definition
the less substituted alkene that results from an E2 rxn
Term
this is usually the major product of an E2 rxn
Definition
Zaitsev (more substituted) product
Term
an example of when the Hofmann (less substituted) product is favored by an E2 rxn
Definition
when it's carried out with a sterically hindered base
Term
some sterically hindered bases that cause the Hofmann (less substituted) product to be favored in an E2 rxn
Definition
-potassium tert-butoxide (t-BuOK)
-lithium diisopropylamide (LDA)
Term
stereoselective
Definition
rxn produces 2 isomers in unequal amounts
Term
stereospecific
Definition
rxn that produces 1 stereoisomer of an alkene as a result of an E2 rxn
Term
the conformation an alkane must take on for an E2 rxn to take place
Definition
antiperiplanar
Term
how an E1 rxn occurs
Definition
leaving group leaves, generating a carbocation intermediate, which then loses a proton in a separate step
Term
the meaning of the 1 in E1 rxns
Definition
the 1 means unimolecular, where te rate is dependent only on the concentration of 1 reactant
Term
depiction of the E2 rxn mechanism
Definition
[image]
Term
depiction of the E1 rxn mechanism
Definition
[image]
Term
the type of rxn that competes with E1 rxns
Definition
SN1 rxns
Term
the most reactive alkyl halides in E1 and SN1 rxns
Definition
tertiary
Term
the rate determining step of E1 and SN1 rxns
Definition
formation of the carbocation intermediate
Term
E1 rxns are ______ instead of ______, thus not requiring antiperiplanar geometry
Definition
stereoselective
stereospecific
Term
E1 rxns are stereoselective instead of stereospecific, thus not requiring ______ geometry
Definition
antiperiplanar
Term
how to predict all the product of a rxn that can be substitution or elimination
Definition
1: determine the function of the reagent
2: analyse the substrate and determine the expected mechanism(s)
3: consider regiochemical and stereochemical requirements
Term
the role of the reagent in a substitution rxn
Definition
nucleophile
Term
the role of the reagent in an elimination rxn
Definition
base
Term
when basicity and nucleophilicity parallel each other
Definition
when comparing elements in the same row
Term
why H2N- is a stronger base than OH-
Definition
because O is more eneg, thus OH- can stabilize a charge better than H2N- can
Term
when basicity and nucleophilicity don't parallel each other
Definition
when comparing atoms in the same column
Term
some reagents that function exclusively as nucleophiles
Definition
-halides
-sulfur nucleophiles
Term
some reagents that function exclusively as bases
Definition
-H- -[image]
Term
some reagents that can unction as strong nucleophiles or strong bases
Definition
-HO- -MeO- -EtO- -[image]
Term
some reagents that can function as weak weak nucleophiles or weak bases
Definition
-H2O -MeOH -EtOH
Term
why [image] usually doesn't function as a nucleophile
Definition
because it's sterically hindered, thus favoring E2 over SN2
Term
the types of rxns strong nucleophiles and strong bases are often used for
Definition
SN2 and E2, respectively
Term
the types of rxns weak nucleophiles and weak bases are often used for
Definition
SN1 and E1, respectively
Term
the type of rxn that happens when the only rxn is the nucleophile
Definition
substitution rxns
Term
the rxn mechanism that predominates when a nucleophile is used on a primary substrate
Definition
SN2
Term
the rxn mechanism that predominates when a nucleophile is used on a secondary substrate
Definition
SN2
Term
the rxn mechanism that predominates when a nucleophile is used on a tertiary substrate
Definition
SN1
Term
the rxn mechanism that predominates when a base is used on a primary substrate
Definition
E2
Term
the rxn mechanism that predominates when a base is used on a secondary substrate
Definition
E2
Term
the rxn mechanism that predominates when a base is used on a tertiary substrate
Definition
E2
Term
type of rxn mechanisms that can occur when a strong nucleophile is used
Definition
SN2, but only on primary ad secondary substrates
Term
type of rxn mechanisms that can occur when a strong base is used
Definition
E2; that goes for primary, secondary, and tertiary substrates
Term
regiochemical outcome of SN2
Definition
n'phile attacks the location where the leaving group was attached
Term
regiochemical outcome of SN1
Definition
n'phile attacks location of positive charge in carbocation
Term
regiochemical outcome of E2
Definition
more substituted product is usually favored unless a sterically hindered base is used, in which case the less substituted product would be used
Term
regiochemical outcome of E1
Definition
more substituted product always favored over the less substituted product
Term
stereochemical outcome of SN2
Definition
n'phile replaces leaving group with inversion of configuration
Term
stereochemical outcome of SN1
Definition
n'phile replaces leaving group with racemization
Term
stereochemical outcome of E2
Definition
both stereoselective and stereospecific
Term
stereochemical outcome of E1
Definition
stereoselective
Term
the difference between E1 and E1cB rxns
Definition
in E1 rxns, the X breaks off before the base grabs the H
in E1cB rxns, the base grabs the H before the X breaks off
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