The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(17), С. 12800 - 12811
Опубликована: Авг. 19, 2024
A
series
of
novel
axially
chiral
pyridylidene
amine
(PYE)
ligands
has
been
developed,
and
their
catalytic
capability
demonstrated
in
various
highly
efficient
enantioselective
Pd-catalyzed
asymmetric
allylic
substitutions.
density-functional
theory
(DFT)
study
explains
the
preferential
enantiocontrol
key
transition
states
PYE
ligand-promoted
alkylation.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(9)
Опубликована: Янв. 3, 2023
The
stereodivergent
synthesis
of
allene
compounds
bearing
α,β-adjacent
central
chiralities
has
been
realized
via
the
Pd/Cu-catalyzed
dynamic
kinetic
asymmetric
alkylation
racemic
allenylic
esters.
matched
reactivity
bimetallic
catalytic
system
enables
challenging
reaction
aryl-substituted
acetates
with
sterically
crowded
aldimine
esters
smoothly
under
mild
conditions.
Various
chiral
non-natural
amino
acids
a
terminal
allenyl
group
are
easily
synthesized
in
high
yields
and
excellent
diastereo-
enantioselectivities
(up
to
>20
:
1
dr,
>99
%
ee).
Importantly,
all
four
stereoisomers
product
can
be
readily
accessed
by
switching
configurations
two
metal
catalysts.
Furthermore,
easy
interconversion
between
uncommon
η3
-butadienyl
palladium
intermediate
featuring
weak
C=C/Pd
coordination
bond
stable
Csp2
-Pd
is
beneficial
for
transformation
process
(DyKAT).
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
unknown
Опубликована: Май 17, 2023
Asymmetric
intermolecular
C–H
functionalization
of
pyridines
at
C3
is
unprecedented.
Herein,
we
report
the
first
examples
such
transformations:
specifically,
C3-allylation
via
tandem
borane
and
iridium
catalysis.
First,
borane-catalyzed
pyridine
hydroboration
generates
nucleophilic
dihydropyridines;
then,
dihydropyridine
undergoes
enantioselective
iridium-catalyzed
allylation;
finally,
oxidative
aromatization
with
air
as
oxidant
gives
C3-allylated
pyridine.
This
protocol
provides
direct
access
to
excellent
enantioselectivity
(up
>99%
ee)
suitable
for
late-stage
pyridine-containing
drugs.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(10)
Опубликована: Янв. 4, 2023
Herein,
we
report
a
synthesis
of
cyclohexanones
bearing
multi-continuous
stereocenters
by
combining
copper-catalyzed
asymmetric
conjugate
addition
dialkylzinc
reagents
to
cyclic
enones
with
iridium-catalyzed
allylic
substitution
reaction.
Good
excellent
yields,
diastereoselectivity
and
enantioselectivity
can
be
obtained.
Unlike
the
stereodivergent
construction
adjacent
(1,2-position)
reported
in
literature,
current
reaction
achieve
nonadjacent
(1,3-position)
proper
combination
two
chiral
catalysts
different
enantiomers.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(34)
Опубликована: Июль 3, 2023
Abstract
Herein,
we
report
a
one‐pot
method
for
enantioselective
C−H
allylation
of
pyridines
at
C3
via
tandem
borane
and
palladium
catalysis.
This
involves
borane‐catalyzed
pyridine
hydroboration
to
generate
dihydropyridines,
then
palladium‐catalyzed
the
dihydropyridines
with
allylic
esters,
finally
air
oxidation
allylated
afford
products.
enables
introduction
an
group
excellent
regio‐
enantioselectivities.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(32)
Опубликована: Июнь 15, 2023
Abstract
Asymmetric
cross‐couplings
based
on
1,2‐carbon
migration
from
B‐ate
complexes
have
been
developed
efficiently
to
access
valuable
organoboronates.
However,
enantioselective
reactions
triggered
by
1,2‐boron
shift
remained
be
unaddressed
synthetic
challenge.
Here,
Ir‐catalyzed
asymmetric
allylic
alkylation
enabled
was
developed.
In
this
reaction,
we
disclosed
that
excellent
enantioselectivities
were
achieved
through
an
interesting
dynamic
kinetic
resolution
(DKR)
process
of
carbonates
at
the
elevated
temperature.
Notably,
highly
(bis‐boryl)alkenes
array
diversifications
versatile
molecules.
Extensive
experimental
and
computational
studies
conducted
elucidate
reaction
mechanism
DKR
clarify
origin
enantioselectivities.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(7), С. 3897 - 3902
Опубликована: Фев. 8, 2023
Rh/silane-cocatalyzed
regio-
and
enantioselctive
allylic
cyanomethylation
with
inert
acetonitrile
directly
has
been
developed.
Addition
of
a
catalytic
amount
neutral
silane
reagent
as
an
anion
carrier
is
essential
for
the
success
this
reaction.
The
synthesis
mono-
bis-allylation
products
can
be
switched
by
adjusting
size
substituents
on
silane,
ligands,
temperature.
Chiral
homoallylic
nitriles
could
synthesized
in
above
20:1
branch/linear
ratio,
up
to
98%
yield
>99%
ee.
The Journal of Organic Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 28, 2025
Carboxylic
acids
are
bench-stable
and
readily
available
chemical
feedstocks
that
function
as
optimal
fundamental
synthetic
platforms
for
the
construction
of
C(sp3)–C(sp3)
bonds
via
decarboxylation
processes.
We
present
a
novel
practical
protocol
decarboxylative
alkylation
Morita–Baylis–Hillman
acetates
with
various
carboxylic
photoinduced
iron-mediated
ligand-to-metal
charge
transfer
(LMCT)
process
under
redox-neutral
conditions.
This
method
exhibits
remarkable
tolerance
to
wide
array
acids,
including
primary,
secondary,
tertiary
obviating
requirement
preactivated
radical
precursors.
The
preliminary
mechanistic
analyses
indicate
pathway
is
involved
in
this
catalytic
transformation.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
63(5)
Опубликована: Дек. 15, 2023
The
construction
of
acyclic,
non-adjacent
1,3-stereogenic
centers,
prevalent
motifs
in
drugs
and
bioactive
molecules,
has
been
a
long-standing
synthetic
challenge
due
to
acyclic
nucleophiles
being
distant
from
the
chiral
environment.
In
this
study,
we
successfully
synthesized
highly
valuable
1,2-bis(boronic)
esters
featuring
nonadjacent
1,3-stereocenters.
Notably,
reaction
selectively
produces
migratory
coupling
products
rather
than
alternative
deborylative
allylation
or
direct
byproducts.
This
approach
introduces
new
activation
mode
for
selective
transformations
gem-diborylmethane
asymmetric
catalysis.
Additionally,
found
that
other
gem-diborylalkanes,
previously
challenging
steric
hindrance,
also
participated
reaction.
incorporation
1,2-bis(boryl)alkenes
facilitated
diversification
alkenyl
two
boron
moieties
our
target
compounds,
thereby
enabling
access
broad
array
versatile
molecules.
DFT
calculations
were
performed
elucidate
mechanism
shed
light
on
factors
responsible
observed
excellent
enantioselectivity
diastereoselectivity.
These
determined
arise
ligand-substrate
repulsions
syn-addition
transition
state.
Organic Letters,
Год журнала:
2023,
Номер
25(8), С. 1246 - 1251
Опубликована: Фев. 23, 2023
Chiral
γ-lactam-containing
skeletons
are
important
motifs
in
bioactive
natural
products,
pharmaceuticals,
and
molecules.
Herein,
we
report
a
general
modular
platform
to
access
chiral
γ-lactam
compounds
via
an
ITU/Ir
cooperatively
catalyzed
[3
+
2]
asymmetric
annulation
reaction
of
vinyl
aziridines
with
pentafluorophenyl
esters.
Through
the
Lewis
base
transition
metal
cooperative
catalytic
regime,
broad
range
optically
active
γ-lactams
were
generated
good
yields
(up
92%)
high
induction
98%
ee).
Furthermore,
utility
this
synthetic
protocol
was
also
demonstrated
by
expedient
preparation
diverse
enantioenriched
architectures.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(34), С. 23674 - 23679
Опубликована: Авг. 19, 2024
The
installation
of
vicinal
quaternary
centers
with
absolute
stereocontrol
constitutes
a
considerable
challenge
in
organic
synthesis.
Herein,
we
introduce
novel
[Cp*Ru(MeCN)