Journal of the American Chemical Society,
Год журнала:
2018,
Номер
140(45), С. 15206 - 15218
Опубликована: Окт. 23, 2018
The
mechanism
of
the
aryl
iodide-catalyzed
asymmetric
migratory
geminal
difluorination
β-substituted
styrenes
(Banik
et
al.
Science
2016,
353,
51)
has
been
explored
with
density
functional
theory
computations.
computed
consists
(a)
activation
iodoarene
difluoride
(ArIF2),
(b)
enantiodetermining
1,2-fluoroiodination,
(c)
bridging
phenonium
ion
formation
via
SN2
reductive
displacement,
and
(d)
regioselective
fluoride
addition.
According
to
computational
model,
ArIF2
intermediate
is
stabilized
through
halogen−π
interactions
between
electron-deficient
iodine(III)
center
benzylic
substituents
at
catalyst
stereogenic
centers.
Interactions
ester
carbonyl
groups
(I(III)+···O)
are
not
observed
in
unactivated
complex,
but
do
occur
upon
hydrogen-bonding
external
Brønsted
acid
(HF).
1,2-fluoroiodination
occurs
alkene
complexation
electrophilic,
cationic
I(III)
followed
by
C–F
bond
anti
forming
C–I
bond.
bound
olefin
adopt
a
spiro
arrangement
favored
transition
structures
nearly
periplanar
disfavored
structures.
Multiple
attractive
non-covalent
interactions,
including
slipped
π···π
stacking,
C–H···O,
C–H···π
found
underlie
high
induction.
chemoselectivity
for
1,1-difluorination
versus
1,2-difluorination
controlled
mainly
(1)
steric
effect
substituent
on
olefinic
double
(2)
nucleophilicity
oxygen
substrate.
Organic Letters,
Год журнала:
2019,
Номер
21(8), С. 2654 - 2657
Опубликована: Март 29, 2019
A
first
example
of
low-energy
blue-light-mediated
formal
Doyle–Kirmse
reaction
for
gem-difluoroallylation
aryl
diazoesters
has
been
developed.
variety
highly
functionalized
gem-difluoroallyl
containing
esters
bearing
transformable
sulfur
and
bromine
groups
were
efficiently
assembled
with
broad
substrate
scope
under
mild,
catalyst-free,
additive-free
conditions.
The
represents
a
practical
environmentally
friendly
approach
C–CF2
bond
formation
based
on
rearrangement
strategy,
which
will
find
potential
applications
among
drug
discovery
development.
Angewandte Chemie International Edition,
Год журнала:
2020,
Номер
60(22), С. 12170 - 12191
Опубликована: Сен. 17, 2020
Due
to
their
unique
properties,
fluorinated
scaffolds
are
pivotal
compounds
in
pharmaceuticals,
agrochemicals,
and
materials
science.
Over
the
last
years,
development
of
versatile
strategies
for
selective
synthesis
molecules
by
direct
C-H
bond
functionalization
has
attracted
a
lot
attention.
In
particular,
design
novel
transformations
based
on
radical
process
was
bottleneck
distal
reactions,
offering
synthetic
solutions
introduction
groups.
This
Minireview
highlights
major
contributions
this
blossoming
field.
The
new
methodologies
remote
aliphatic
derivatives
with
various
groups
1,5-hydrogen
atom
transfer
β-fragmentation
reaction
will
be
showcased
discussed.
Journal of the American Chemical Society,
Год журнала:
2018,
Номер
140(45), С. 15206 - 15218
Опубликована: Окт. 23, 2018
The
mechanism
of
the
aryl
iodide-catalyzed
asymmetric
migratory
geminal
difluorination
β-substituted
styrenes
(Banik
et
al.
Science
2016,
353,
51)
has
been
explored
with
density
functional
theory
computations.
computed
consists
(a)
activation
iodoarene
difluoride
(ArIF2),
(b)
enantiodetermining
1,2-fluoroiodination,
(c)
bridging
phenonium
ion
formation
via
SN2
reductive
displacement,
and
(d)
regioselective
fluoride
addition.
According
to
computational
model,
ArIF2
intermediate
is
stabilized
through
halogen−π
interactions
between
electron-deficient
iodine(III)
center
benzylic
substituents
at
catalyst
stereogenic
centers.
Interactions
ester
carbonyl
groups
(I(III)+···O)
are
not
observed
in
unactivated
complex,
but
do
occur
upon
hydrogen-bonding
external
Brønsted
acid
(HF).
1,2-fluoroiodination
occurs
alkene
complexation
electrophilic,
cationic
I(III)
followed
by
C–F
bond
anti
forming
C–I
bond.
bound
olefin
adopt
a
spiro
arrangement
favored
transition
structures
nearly
periplanar
disfavored
structures.
Multiple
attractive
non-covalent
interactions,
including
slipped
π···π
stacking,
C–H···O,
C–H···π
found
underlie
high
induction.
chemoselectivity
for
1,1-difluorination
versus
1,2-difluorination
controlled
mainly
(1)
steric
effect
substituent
on
olefinic
double
(2)
nucleophilicity
oxygen
substrate.
