The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 19, 2024
Herein,
a
cobalt-catalyzed
intramolecular
enantioselective
reductive
Heck
reaction
is
disclosed.
Starting
from
N-ortho-iodoaryl-2-(trifluoromethyl)acrylamides,
plethora
of
chiral
oxindoles
bearing
trifluoromethylated
quaternary
stereogenic
centers
at
the
C3-position
are
achieved
in
moderate
to
good
yields
(up
88%
yield)
and
excellent
enantioselectivities
94%
ee)
by
employing
zinc/silane
as
reducing
agent.
Other
than
trifluoromethyl
group,
number
alkyl,
aryl,
ester
groups
were
also
obtained
albeit
relatively
lower
(68–78%
ee).
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(28), С. 15456 - 15464
Опубликована: Июнь 12, 2023
Novel-substituted
pyrrolidine
derivatives
are
widely
used
in
drugs
and
bioactive
molecules.
The
efficient
synthesis
of
these
valuable
skeletons,
especially
enantiopure
derivatives,
is
still
recognized
as
a
key
bottleneck
to
overcome
chemical
synthesis.
Herein,
we
report
highly
catalyst-tuned
regio-
enantioselective
hydroalkylation
reaction
for
the
divergent
chiral
C2-
C3-alkylated
pyrrolidines
through
desymmetrization
readily
available
3-pyrrolines.
catalytic
system
consists
CoBr2
with
modified
bisoxazoline
(BOX)
ligand,
which
can
achieve
asymmetric
C(sp3)-C(sp3)
coupling
via
distal
stereocontrol,
providing
series
high
efficiency.
Moreover,
nickel
allows
synthesize
C2-alkylated
tandem
alkene
isomerization/hydroalkylation
reaction.
This
method
uses
catalysts,
BOX
ligands,
reagents,
delivering
enantioenriched
2-/3-alkyl
substituted
excellent
enantioselectivity
(up
97%
ee).
We
also
demonstrate
compatibility
this
transformation
complex
substrates
derived
from
molecules
good
efficiency,
offers
distinct
entry
more
functionalized
N-heterocycles.
Advanced Synthesis & Catalysis,
Год журнала:
2023,
Номер
365(5), С. 620 - 681
Опубликована: Янв. 17, 2023
Abstract
This
review
updates
the
field
of
enantioselective
domino
reactions
promoted
by
chiral
catalysts
derived
from
noble
metals,
including
palladium,
silver,
rhodium,
ruthenium,
iridium
and
gold,
published
since
beginning
2019.
It
illustrates
how
much
a
diversity
these
allow
unprecedented
asymmetric
many
types
to
be
achieved
with
excellent
enantioselectivity,
giving
direct
access
wide
variety
complex
molecules.
magnified
image
Organic Letters,
Год журнала:
2023,
Номер
25(33), С. 6122 - 6127
Опубликована: Авг. 14, 2023
Herein,
we
describe
a
nickel-catalyzed
asymmetric
dearomative
aryl-difluoroallylation
reaction
of
indoles
with
α-trifluoromethyl
alkenes
as
an
electrophilic
coupling
partner.
The
proceeds
via
cascade
sequence
involving
Heck
cyclization
and
reductive
allylic
defluorination.
A
series
gem-difluoroallyl
substituted
indolines
are
obtained
in
moderate
to
good
yields
(36-77%
yield)
excellent
enantioselectivity
(up
99%
ee).
features
broad
functional
group
tolerance,
scaled-up
synthesis,
late-stage
diversification.
Organic Letters,
Год журнала:
2024,
Номер
26(18), С. 3739 - 3743
Опубликована: Апрель 29, 2024
An
enantioselective
Pd-catalyzed
intramolecular
dearomative
reductive
Heck
reaction
of
N-(o-bromoaryl)
indole-3-carboxamide
is
developed.
By
employing
Pd(dba)2/SPINOL-based
phosphoramidite
as
the
chiral
catalyst
and
HCO2Na
hydride
source,
a
series
enantioenriched
spiro
indolines
bearing
vicinal
stereocenters
were
afforded
in
moderate
to
good
yields
with
excellent
enantioselectivities.
The
formal
tetrasubstituted
alkene
β-hydrogens
therefore
realized
by
inhibiting
β-H
elimination.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(11), С. 7552 - 7560
Опубликована: Май 28, 2024
Herein,
a
palladium-catalyzed
diastereoselective
dearomatization/cross-coupling
cyclization
reaction
between
N-arylacyl
indoles
and
(E)-β-chlorovinyl
ketones
is
reported.
Through
this
cyclization/cycloisomerization
cascade,
series
of
furan-containing
indolines
were
obtained
in
yields
up
to
95%.
The
features
readily
accessible
starting
materials,
benzyl
Pd(II)-catalyzed
cycloisomerization
ketones,
the
sequential
formation
three
bonds
bis-heterocycles,
excellent
diastereoselectivity.
More
importantly,
carbene–secondary
migratory
insertion
proven
be
critical
process
cyclizations.
A
palladium-catalyzed
reaction
of
indoles
with
cyanoacetate
salts
enables
the
synthesis
2,6-disubstituted
indolines
via
tandem
dearomatization/decarboxylative
cyanomethylation.
Remarkably,
this
is
first
example
indole
difunctionalization
at
C2
and
C6
positions.
Moreover,
methodology
extends
to
cyclization/decarboxylative
cyanomethylation
aryl
halide-tethered
alkenes.
Organic Letters,
Год журнала:
2024,
Номер
26(43), С. 9389 - 9394
Опубликована: Окт. 21, 2024
Until
now,
palladium-catalyzed
dearomative
Heck
reactions
of
indoles
were
largely
limited
to
β-H
elimination
and
nucleophilic
capture
the
transient
alkyl-Pd(II)
species.
Herein,
we
disclose
a
novel
Heck/C(sp
Indoles
represent
one
of
the
most
robust
and
synthetically
versatile
classes
heteroaromatic
compounds.
However,
stereoselective
conversion
planar
indole
rings
into
three-dimensional
indoline
skeletons
bearing
multiple
stereogenic
centers
remains
a
persistent
challenge
in
organic
synthesis.
Herein,
we
describe
an
intermolecular
catalytic
asymmetric
dearomatization
simple
indoles
via
palladium-catalyzed
three-component
cross-coupling
reaction.
By
using
readily
accessible
diazonium
salts
aromatic
boronic
acids
as
arylative
reagents
under
ligand-swap
strategy,
this
method
enables
efficient
construction
2,3-diarylated
indolines.
Mechanistic
studies
reveal
that
chiral
BiOx
ligand
governs
highly
migratory
insertion
aryl-palladium
intermediate
indole’s
C═C
double
bond
with
complete
diastereo-
regioselectivity,
whereas
achiral
fumarate
facilitates
reductive
elimination
step,
corroborated
by
density
functional
theory
calculations.
Furthermore,
protocol
is
extended
to
dearomative
diarylation
benzofurans,
affording
2,3-dihydrobenzofuran
derivatives
high
stereocontrol.
