Angewandte Chemie,
Год журнала:
2024,
Номер
136(22)
Опубликована: Март 22, 2024
Abstract
The
use
of
gem
‐difluorinated
cyclopropanes
(
‐DFCPs)
as
fluoroallyl
surrogates
under
transition‐metal
catalysis
has
drawn
considerable
attention
recently
but
such
reactions
are
restricted
to
producing
achiral
or
racemic
mono‐fluoroalkenes.
Herein,
we
report
the
first
enantioselective
allylation
indoles
rhodium
with
‐DFCPs.
This
reaction
shows
exceptional
branched
regioselectivity
towards
‐DFCPs,
which
provides
an
efficient
route
enantioenriched
fluoroallylated
wide
substrate
scope
and
good
functional
group
tolerance.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(23)
Опубликована: Апрель 4, 2023
Defluorinative
manipulation
of
polyfluorinated
molecules
has
shown
great
promise
due
to
its
granting
synthetic
versatility
inert
C-F
bonds.
The
development
chemo-,
stereo-
and
regioselective
strategies
realize
highly
efficient
formation
either
the
linear/branched
or
E/Z
products
from
gem-difluorocyclopropanes
(gem-F2
CPs)
is
a
challenging
task.
Herein,
we
have
realized
palladium/NHC-catalyzed
fluoroallylation/annulation
hydrazones
with
gem-F2
CPs
that
incorporate
hydrazone
N2
moiety
into
products.
thermodynamically
unstable
fluorinated
E-allylation
aryl
ketone
were
obtained
for
first
time,
while
di-alkyl
yielded
monofluorinated
branched
selectivity
under
similar
reaction
conditions.
With
aldehyde
hydrazones,
two
kinds
pyrazoles
via
defluorinative
allylation/annulation
cascade,
in
which
different
carbon
atoms
could
be
incorporated
pyrazole
rings
regiospecifically.
DFT
calculations
revealed
divergent
was
kinetically
controlled
final
C-C
bond
proceeded
through
7-membered
TS.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(32)
Опубликована: Июнь 20, 2023
Direct
synthesis
of
gem-difluorinated
carbocyclic
molecules
represents
a
longstanding
challenge
in
organic
chemistry.
Herein,
Rh-catalyzed
[3+2]
cycloaddition
reaction
between
readily
available
cyclopropanes
(gem-DFCPs)
and
internal
olefins
has
been
developed,
enabling
the
efficient
cyclopentanes
with
good
functional
group
compatibility,
excellent
regioselectivity
diastereoselectivity.
The
resulting
products
can
undergo
downstream
transformations
to
access
various
mono-fluorinated
cyclopentenes
cyclopentanes.
This
demonstrates
use
gem-DFCPs
as
type
"CF2
"
C3
synthon
for
under
transition
metal
catalysis,
which
provides
potential
strategy
synthesizing
other
molecules.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(42)
Опубликована: Авг. 12, 2023
Abstract
An
unprecedented
Pd‐catalyzed
fluorinative
bifunctionalization
of
aziridines
and
azetidines
was
successfully
developed
via
regioselective
C−C
C−F
bond
cleavage
gem‐difluorocyclopropanes,
leading
to
various
β,β′‐bisfluorinated
amines
β,γ‐bisfluorinated
amines.
This
reaction
achieved
by
incorporating
a
2‐fluorinated
allyl
group
fluorine
atom
scissored
from
gem‐difluorocyclopropane
in
100
%
economy
for
the
first
time.
The
mechanistic
investigations
indicated
that
underwent
amine
attacking
palladium
complex
generate
η
2
‐coordinated
N‐allyl
aziridine
followed
fluoride
ligand
transfer
affording
final
β‐
γ‐fluorinated
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(22)
Опубликована: Март 22, 2024
Abstract
The
use
of
gem
‐difluorinated
cyclopropanes
(
‐DFCPs)
as
fluoroallyl
surrogates
under
transition‐metal
catalysis
has
drawn
considerable
attention
recently
but
such
reactions
are
restricted
to
producing
achiral
or
racemic
mono‐fluoroalkenes.
Herein,
we
report
the
first
enantioselective
allylation
indoles
rhodium
with
‐DFCPs.
This
reaction
shows
exceptional
branched
regioselectivity
towards
‐DFCPs,
which
provides
an
efficient
route
enantioenriched
fluoroallylated
wide
substrate
scope
and
good
functional
group
tolerance.
Chemical Communications,
Год журнала:
2024,
Номер
60(28), С. 3764 - 3773
Опубликована: Янв. 1, 2024
This
feature
article
summarizes
our
efforts
towards
developing
Rh-catalyzed
reactions
of
gem
-difluorinated
cyclopropanes,
briefly
discussing
the
design,
selectivity,
mechanisms
and
future
research
prospects.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(23)
Опубликована: Фев. 27, 2024
A
novel
enantioselective
Tsuji-Trost-type
cross
coupling
reaction
between
gem-difluorinated
cyclopropanes
and
N-unprotected
amino
acid
esters
enabled
by
synergistic
Pd/Ni/chiral
aldehyde
catalysis
is
presented
herein.
This
transformation
streamlined
the
diversity-oriented
synthesis
(DOS)
of
optically
active
α-quaternary
α-amino
bearing
a
linear
2-fluoroallylic
motif,
which
served
as
an
appealing
platform
for
construction
other
valuable
enantioenriched
compounds.
The
key
intermediates
were
confirmed
HRMS
detection,
while
DFT
calculations
revealed
that
excellent
enantioselectivity
was
attributed
to
stabilizing
non-covalent
interactions
Pd(II)-π-fluoroallyl
species
Ni(II)-Schiff
base
complex.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Май 21, 2024
Abstract
Transition-metal
catalyzed
allylic
substitution
reactions
of
alkenes
are
among
the
most
efficient
methods
for
synthesizing
diene
compounds,
driven
by
inherent
preference
an
inner-sphere
mechanism.
Here,
we
present
a
demonstration
outer-sphere
mechanism
in
Rh-catalyzed
reaction
simple
using
gem
-difluorinated
cyclopropanes
as
allyl
surrogates.
This
unconventional
offers
opportunity
fluorine
recycling
via
C
−
F
bond
cleavage/reformation,
ultimately
delivering
carbofluorination
products.
The
developed
method
tolerates
wide
range
alkenes,
providing
access
to
secondary,
tertiary
fluorides
and
-difluorides
with
100%
atom
economy.
DFT
calculations
reveal
that
formation
goes
through
unusual
nucleophilic
allyl-Rh
species
instead
migration
insertion,
generated
carbon
cation
then
forms
tetrafluoroborate
fluoride
shuttle.
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(6), С. 3787 - 3793
Опубликована: Фев. 24, 2023
Fluorinated
compounds
have
found
widespread
applications
in
pharmaceuticals,
agrochemicals,
and
materials
science.
Precise
construction
of
α-difluoromethylene
ether
(CF2-O)
moiety
organic
molecules
is
high
demand.
Herein,
a
visible
light-promoted
reaction
protocol
for
the
synthesis
from
gem-difluorocyclopropane
described.
The
key
ring-opening
step
induced
by
hyperconjugative
interaction
cyclopropane
with
photo-oxidized
aromatic
rings.
This
easy
scale-up,
products
bearing
synthetic
handle
enable
their
further
manipulation.
