Chemical Science,
Journal Year:
2022,
Volume and Issue:
13(42), P. 12419 - 12425
Published: Jan. 1, 2022
The
control
of
linear/branched
selectivity
is
one
the
major
focuses
in
transition-metal
catalyzed
allyl-allyl
cross-coupling
reactions,
which
bond
connection
occurs
at
terminal
site
both
allyl
fragments
forming
different
types
1,5-dienes.
Herein,
terminal/internal
regioselectivity
investigated
and
found
to
be
switchable
reactions
between
gem-difluorinated
cyclopropanes
allylboronates.
controlled
arises
from
fine-tuning
rhodium
catalytic
system.
Fluorinated
1,3-dienes,
1,4-dienes
1,5-dienes
are
therefore
produced
good
yields
with
respectively
isomerized
terminal,
internal,
regioselectivity.
Angewandte Chemie International Edition,
Journal Year:
2021,
Volume and Issue:
60(23), P. 13098 - 13104
Published: March 23, 2021
Abstract
Conventional
approaches
for
Pd‐catalyzed
ring‐opening
cross‐couplings
of
gem
‐difluorocyclopropanes
with
nucleophiles
predominantly
deliver
the
β‐fluoroalkene
scaffolds
(linear
selectivity).
Herein,
we
report
a
cooperative
strategy
that
can
completely
switch
reaction
selectivity
to
give
alkylated
α‐fluoroalkene
skeletons
(branched
The
unique
reactivity
hydrazones
enables
analogous
inner‐sphere
3,3′‐reductive
elimination
driven
by
denitrogenation,
as
well
assistance
steric‐embedded
N
‐heterocyclic
carbene
ligand,
are
key
regioselectivity.
A
wide
range
derived
from
naturally
abundant
aryl
and
alkyl
aldehydes
applicable,
various
‐difluorocyclopropanes,
including
modified
pharmaceutical
biological
molecules,
be
efficiently
functionalized
high
value
α‐fluorinated
alkene
motifs
under
mild
conditions.
Angewandte Chemie International Edition,
Journal Year:
2021,
Volume and Issue:
60(19), P. 10626 - 10631
Published: Feb. 18, 2021
Herein,
we
report
a
rhodium
catalyzed
directing-group
free
regioselective
C-H
allylation
of
simple
arenes.
Readily
available
gem-difluorinated
cyclopropanes
can
be
employed
as
highly
reactive
allyl
surrogates
via
sequence
C-C
and
C-F
bond
activation,
providing
arene
derivatives
in
good
yields
with
high
regioselectivity
under
mild
conditions.
The
robust
methodology
enables
facile
late-stage
functionalization
complex
bioactive
molecules.
efficiency
this
reaction
is
also
demonstrated
by
the
turnover
number
(TON,
up
to
1700)
catalyst
on
gram-scale
experiments.
Preliminary
success
kinetic
resolution
transformation
achieved,
promising
access
enantio-enriched
cyclopropanes.
Organic Letters,
Journal Year:
2020,
Volume and Issue:
22(4), P. 1414 - 1419
Published: Feb. 3, 2020
Herein,
we
describe
a
palladium-catalyzed
alkynylation
of
gem-difluorinated
cyclopropanes
via
C–C
bond
activation/C–F
cleavage,
followed
by
C–C(sp)
coupling.
The
new
approach
proceeds
with
broad
substrate
scope
under
mild
reaction
conditions,
whereas
both
1,1-disubstituted
and
complex-molecule-modified
react
smoothly
high
stereoselectivity.
developed
method
provides
efficient
convenient
ways
access
to
diversity
important
fluorinated
enynes
arenes
slightly
modification
the
conditions.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(9), P. 3259 - 3263
Published: April 19, 2021
Monofluoroalkenes
normally
act
as
metabolically
stable
bioisosteres
for
amide
groups
(-NH-CO-)
and
have
widespread
applications
in
drug
discovery.
Additionally,
they
are
widely
used
building
blocks
organic
synthesis.
In
this
study,
the
Cu/Pd-catalyzed
cis-borylfluoroallylation
of
alkynes
was
achieved,
providing
a
modular
general
tactic
preparation
monofluorinated
alkene
scaffolds
with
high
regioselectivity
stereoselectivity.
Moreover,
an
array
synthetic
can
be
generated
by
downstream
transformations.
ACS Catalysis,
Journal Year:
2021,
Volume and Issue:
11(19), P. 11960 - 11965
Published: Sept. 13, 2021
A
cross-electrophile
coupling
between
gem-difluorinated
cyclopropanes
and
2,2-difluorovinyl
tosylate
via
dual
Ni/Pd
cooperative
catalysis
under
mild
reaction
conditions
is
presented.
Various
structurally
unique
organofluorine
compounds
bearing
both
monofluoroalkene
gem-difluoroalkene
moieties
can
be
effectively
afforded
in
good
yields
with
a
high
(Z)-selectivity.
The
synthetic
utility
of
this
protocol
has
been
successfully
demonstrated
by
the
late-stage
modification
series
complex
bioactive
molecules.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(12), P. 4920 - 4924
Published: June 4, 2021
A
palladium-catalyzed
C-H
allylation
of
electron-deficient
polyfluoroarenes
with
gem-difluorinated
cyclopropanes
is
reported.
It
provides
a
useful
and
facile
approach
to
2-fluoroallylic
in
moderate
excellent
yields
high
Z-selectivity.
In
addition,
this
new
has
good
functional
group
compatibility
broad
substrate
scope.
Organic Letters,
Journal Year:
2022,
Volume and Issue:
24(11), P. 2093 - 2098
Published: March 11, 2022
Palladium-catalyzed
synthesis
of
3-acyl
and
-allyl
indoles
has
been
realized
by
merging
nucleophilic
cyclization
ortho-alkynylanilines
with
ring
opening
three-membered
rings
such
as
cyclopropenones
gem-difluorinated
cyclopropanes.
These
functionalized
were
obtained
in
moderate
to
high
yields
stereoselectivity
both
cases.
This
protocol
provides
an
alternative
method
toward
under
mild
redox-neutral
conditions.
ACS Catalysis,
Journal Year:
2022,
Volume and Issue:
12(11), P. 6495 - 6505
Published: May 17, 2022
Controlling
the
selectivity
of
synthetically
useful
reactions
has
been
a
longstanding
objective
organic
chemistry.
We
report
regiodivergent
synthetic
protocol
allowing
access
to
diverse
fluorinated
1,5-dienes
through
Pd/NHC-catalyzed
ring-opening
allylation
gem-difluorocyclopropanes.
Density
functional
theory
(DFT)
calculations
on
regioselectivity-determining
transition
states
provided
critical
insight
into
design
NHC
ligand
for
switching
regioselectivity.
Consistent
with
DFT
predictions,
N-heterocyclic
carbene
(NHC)
ligands
bulky
ortho
substituents
favored
branched
allylation,
IHept
providing
>
20:1
branched/linear
less
hindered
such
as
IMes
thermodynamically
more
stable
linear
products.
were
able
carry
out
late-stage
modification
various
complex
molecules
using
this
protocol.
Our
ligand-controlled
approach
provides
efficient
regioisomeric
from
same
starting
materials
and
constitutes
valuable
addition
toolbox
diversity-oriented
synthesis.
ACS Catalysis,
Journal Year:
2022,
Volume and Issue:
12(15), P. 8857 - 8867
Published: July 10, 2022
The
unique
properties
of
the
fluorine-containing
compounds
and
their
widespread
applications
raise
demand
for
dependable
synthetic
methods
on
precise
introduction
substituents
into
organic
molecules.
Herein,
a
site-divergent
fluoroallylation
olefins
that
can
incorporate
fluoroallyl
motif
different
alkenyl
C–H
sites
is
disclosed.
gem-Difluorinated
cyclopropanes
are
employed
as
sources
via
rhodium-catalyzed
C–C
bond
activation.
This
strategy
provide
two
regioisomeric
fluorinated
skipped
dienes
in
good
yields
with
excellent
site-selectivity.
resulting
products
serve
useful
building
blocks
to
access
various
molecules
isosteric
β,
γ-unsaturated
amides,
which
promising
be
exploited
medicinal
chemistry.
Mechanistic
studies
revealed
electronic
property
rhodium
catalysts
crucial
controllable
site-selectivity,
providing
more
insights
beyond
methodology
tuning
selectivity
metal
catalysts.
ChemCatChem,
Journal Year:
2022,
Volume and Issue:
14(24)
Published: Aug. 11, 2022
Abstract
gem
‐Difluorocyclopropanes
(F
2
CPs)
have
aroused
considerable
attention
not
only
from
the
structural
perspective
but
also
due
to
their
ability
participate
in
various
valuable
transformations.
This
Review
summarizes
advances
catalytic
ring‐opening
reactions
of
‐F
CPs,
especially
emphasizing
reactivities
and
applications
those
non‐activated
ones
under
transition‐metal
catalysis.
Their
achievements,
synthetic
limitations
are
discussed
with
aim
stimulate
enthusiasm
for
further
development.
