Chemistry - A European Journal,
Journal Year:
2017,
Volume and Issue:
23(72), P. 18125 - 18128
Published: Sept. 25, 2017
Abstract
A
technically
simple
procedure
for
direct
C−H
difluoromethylation
of
heteroaromatic
compounds
using
off‐the‐shelf
difluoroacetic
acid
as
the
difluoromethylating
reagent
has
been
developed.
Mono‐difluoromethylation
versus
bis‐difluoromethylation
is
controlled
result
reaction
temperature.
The
reactions
described
here
enable
access
to
late‐stage
mono‐
and
preparation
tool
chemical
biology
provide
this
hitherto
untapped
substituent
drug
discovery.
Angewandte Chemie International Edition,
Journal Year:
2017,
Volume and Issue:
56(33), P. 9971 - 9975
Published: June 28, 2017
A
new
method
for
the
on-site
preparation
of
tetrafluoroethylene
(TFE)
and
a
procedure
its
efficient
use
in
pentafluoroethylation
by
fluoride
addition
were
developed
using
simple
two-chamber
system.
The
TFE
was
accomplished
dimerization
difluorocarbene
derived
from
(trifluoromethyl)trimethylsilane
(TMSCF3
)
under
mild
conditions.
Other
fluoroalkylation
reactions,
such
as
(aryloxy)tetrafluoroethylation
tetrafluoroethylation
processes,
also
achieved
similar
approach.
This
work
not
only
demonstrates
convenient
safe
approach
generation
academic
laboratories,
but
provides
strategy
pentafluoroethylation.
Journal of the American Chemical Society,
Journal Year:
2018,
Volume and Issue:
140(45), P. 15206 - 15218
Published: Oct. 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.
Angewandte Chemie International Edition,
Journal Year:
2020,
Volume and Issue:
60(22), P. 12170 - 12191
Published: Sept. 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.
Advanced Synthesis & Catalysis,
Journal Year:
2020,
Volume and Issue:
362(20), P. 4256 - 4292
Published: Aug. 4, 2020
Abstract
This
review
summarizes
the
progress
in
fluorination
and
fluoroalkylation
of
electron‐rich
systems
with
diverse
fluorine
(F)
fluoroalkyl
(R
fn
)
reagents
employing
hypervalent
iodine
compounds
as
initiators
last
few
decades.
Because
strong
electrophilicity,
high
oxidizing
properties,
low
toxicity,
air
moisture
stability,
ready
availability,
ease
handling,
mild
reaction
conditions,
have
been
widely
utilized
modern
organic
chemistry.
In
particular,
use
to
initiate
C−F
C−R
=CF
2
H,
CF
3
,
perfluoroalkyl,
OCH
SCF
SeCF
etc)
bond
formation
has
increasingly
developed.
these
reactions,
behave
powerful
oxidants
or
electrophiles
activate
fluorination/fluoroalkylation
reagents,
transition‐metal
catalysts,
substrates
situ
form
electrophilic
radical
intermediates,
which
subsequently
participate
fluorination,
difluoromethylation,
trifluoromethylation,
perfluoroalkylation,
trifluoroethoxylation,
fluoroalkylthiolation,
trifluoromethylselenolation
others
under
conditions.
Although
great
achievements
made
this
area,
they
are
just
initial
phase
still
require
a
wide
scope
for
improvement.
It
is
anticipated
that
will
draw
much
attention
from
chemistry
community
inspire
more
contributions
development
new
hypervalent‐iodine‐mediated
reactions.
magnified
image
Chemistry - A European Journal,
Journal Year:
2017,
Volume and Issue:
23(72), P. 18125 - 18128
Published: Sept. 25, 2017
Abstract
A
technically
simple
procedure
for
direct
C−H
difluoromethylation
of
heteroaromatic
compounds
using
off‐the‐shelf
difluoroacetic
acid
as
the
difluoromethylating
reagent
has
been
developed.
Mono‐difluoromethylation
versus
bis‐difluoromethylation
is
controlled
result
reaction
temperature.
The
reactions
described
here
enable
access
to
late‐stage
mono‐
and
preparation
tool
chemical
biology
provide
this
hitherto
untapped
substituent
drug
discovery.
