Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(19), С. 12895 - 12900
Опубликована: Май 2, 2024
A
nickel
complex
of
chiral
bisoxazolines
catalyzed
the
stereoselective
reductive
arylation
ketones
in
high
enantioselectivity.
range
common
acyclic
and
cyclic
reacted
without
aid
directing
groups.
Mechanistic
studies
using
isolated
a
bis(oxazoline)
(L)Ni(Ar)Br
revealed
that
Mn
reduction
was
not
needed,
while
Lewis
acidic
titanium
alkoxides
were
critical
to
ketone
insertion.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(15), С. 8689 - 8699
Опубликована: Апрель 4, 2023
While
the
oxidative
addition
of
Ni(I)
to
aryl
iodides
has
been
commonly
proposed
in
catalytic
methods,
an
in-depth
mechanistic
understanding
this
fundamental
process
is
still
lacking.
Herein,
we
describe
a
detailed
study
using
electroanalytical
and
statistical
modeling
techniques.
Electroanalytical
techniques
allowed
rapid
measurement
rates
for
diverse
set
iodide
substrates
four
classes
catalytically
relevant
complexes
(Ni(MeBPy),
Ni(MePhen),
Ni(Terpy),
Ni(BPP)).
With
>200
experimental
rate
measurements,
were
able
identify
essential
electronic
steric
factors
impacting
through
multivariate
linear
regression
models.
This
led
classification
mechanisms,
either
three-center
concerted
or
halogen-atom
abstraction
pathway
based
on
ligand
type.
A
global
heat
map
predicted
was
created
shown
applicable
better
reaction
outcome
case
Ni-catalyzed
coupling
reaction.
Accounts of Chemical Research,
Год журнала:
2024,
Номер
57(5), С. 751 - 762
Опубликована: Фев. 12, 2024
ConspectusAfter
decades
of
palladium
dominating
the
realm
transition-metal-catalyzed
cross-coupling,
recent
years
have
witnessed
exciting
advances
in
development
new
nickel-catalyzed
cross-coupling
reactions
to
form
C(sp3)
centers.
Nickel
possesses
distinct
properties
compared
with
palladium,
such
as
facile
single-electron
transfer
electrophiles
and
rapid
C–C
reductive
elimination
from
NiIII.
These
properties,
among
others,
make
nickel
particularly
well-suited
for
(RCC)
which
two
are
coupled
an
exogenous
reductant
is
used
turn
over
metal
catalyst.
Ni-catalyzed
RCCs
use
readily
available
stable
starting
materials
exhibit
good
functional
group
tolerance,
makes
them
appealing
applications
synthesis
complex
molecules.
Building
upon
foundational
work
by
groups
Kumada,
Durandetti,
Weix,
well
advancements
enantioselective
redox-neutral
cross-couplings
led
Fu
co-workers,
we
initiated
a
program
explore
feasibility
developing
highly
RCCs.
Our
research
has
also
been
driven
keen
interest
unraveling
factors
contributing
enantioinduction
electrophile
activation
seek
avenues
advancing
our
understanding
further
these
reactions.In
first
part
this
Account,
organize
reported
methods
on
basis
identity
electrophiles,
including
benzylic
chlorides,
N-hydroxyphthalimide
(NHP)
esters,
α-chloro
esters
nitriles.
We
highlight
how
selection
specific
chiral
ligands
plays
pivotal
role
achieving
high
cross-selectivity
enantioselectivity.
In
addition,
show
that
reduction
can
be
accomplished
not
only
heterogeneous
reductants,
Mn0,
but
soluble
organic
tetrakis(dimethylamino)ethylene
(TDAE),
electrochemically.
The
homogeneous
TDAE,
suited
studying
mechanism
transformation.
Although
Account
primarily
focuses
RCCs,
using
trifluoroborate
(BF3K)
salts
radical
precursors
dual-Ni/photoredox
systems.At
end
summarize
relevant
mechanistic
studies
closely
related
asymmetric
alkenylation
developed
laboratory
provide
context
between
others.
discuss
ligand
influence
rates
mechanisms
mode
generation
optimize
yield
RCC.
endeavors
offer
insights
intricate
at
play
goal
rate
improve
substrate
scope
anticipate
share
guidance
field.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(44), С. 23910 - 23917
Опубликована: Окт. 26, 2023
The
merger
of
electrochemistry
and
transition
metal
catalysis
has
emerged
as
a
powerful
tool
to
join
two
electrophiles
in
an
enantioselective
manner.
However,
the
development
electroreductive
cross-couplings
olefins
remains
challenge.
Inspired
by
advantages
synergistic
use
with
nickel
catalysis,
we
present
here
Ni-catalyzed
cross-coupling
acrylates
aryl
halides
alkyl
bromides,
which
affords
chiral
α-aryl
carbonyls
good
excellent
enantioselectivity.
Additionally,
this
catalytic
reaction
can
be
applied
(hetero)aryl
chlorides,
is
difficult
achieve
other
methods.
combination
cyclic
voltammetry
analysis
electrode
potential
studies
suggests
that
NiI
species
activates
oxidative
addition
bromides
single-electron
transfer.
ACS Catalysis,
Год журнала:
2024,
Номер
14(11), С. 9055 - 9076
Опубликована: Май 29, 2024
Metallaphotoredox
catalysis
can
unlock
useful
pathways
for
transforming
organic
reactants
into
desirable
products,
largely
due
to
the
conversion
of
photon
energy
chemical
potential
drive
redox
and
bond
transformation
processes.
Despite
importance
these
processes
cross-coupling
reactions
other
transformations,
their
mechanistic
details
are
only
superficially
understood.
In
this
review,
we
have
provided
a
detailed
summary
various
photoredox
mechanisms
that
been
proposed
date
Ni-bipyridine
(bpy)
complexes,
focusing
separately
on
photosensitized
direct
excitation
reaction
By
highlighting
multiple
key
findings,
depict
how
mechanisms,
which
ultimately
define
substrate
scope,
themselves
defined
by
ground-
excited-state
geometric
electronic
structures
Ni-based
intermediates.
We
further
identify
knowledge
gaps
motivate
future
studies
development
synergistic
research
approaches
spanning
physical,
organic,
inorganic
chemistry
communities.
Chemical Reviews,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 26, 2024
Cross-electrophile
coupling
(XEC),
defined
by
us
as
the
cross-coupling
of
two
different
σ-electrophiles
that
is
driven
catalyst
reduction,
has
seen
rapid
progression
in
recent
years.
As
such,
this
review
aims
to
summarize
field
from
its
beginnings
up
until
mid-2023
and
provide
comprehensive
coverage
on
synthetic
methods
current
state
mechanistic
understanding.
Chapters
are
split
type
bond
formed,
which
include
C(sp
Nature Catalysis,
Год журнала:
2024,
Номер
7(6), С. 733 - 741
Опубликована: Май 7, 2024
Abstract
Nickel
photoredox
catalysis
has
resulted
in
a
rich
development
of
transition-metal-catalysed
transformations
for
carbon–heteroatom
bond
formation.
By
harnessing
light
energy,
the
transition
metal
can
attain
oxidation
states
that
are
difficult
to
achieve
through
thermal
chemistry
catalytic
manifold.
For
example,
nickel
reactions
have
been
reported
both
synthesis
anilines
and
aryl
ethers
from
aryl(pseudo)halides.
However,
oxidative
addition
simple
systems
is
often
sluggish
absence
special,
electron-rich
ligands,
leading
catalyst
decomposition.
Electron-rich
electrophiles
therefore
currently
fall
outside
scope
many
field.
Here
we
provide
conceptual
solution
this
problem
demonstrate
nickel-catalysed
C–heteroatom
bond-forming
arylthianthrenium
salts,
including
amination,
oxygenation,
sulfuration
halogenation.
Because
redox
properties
salts
primarily
dictated
by
thianthrenium,
highly
donors
be
unlocked
using
NiCl
2
under
irradiation
form
desired
C‒heteroatom
bonds.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(22), С. 15331 - 15344
Опубликована: Май 23, 2024
Within
the
context
of
Ni
photoredox
catalysis,
halogen
atom
photoelimination
from
has
emerged
as
a
fruitful
strategy
for
enabling
hydrogen
transfer
(HAT)-mediated
C(sp3)–H
functionalization.
Despite
numerous
synthetic
transformations
invoking
this
paradigm,
unified
mechanistic
hypothesis
that
is
consistent
with
experimental
findings
on
catalytic
systems
and
accounts
radical
formation
facile
C(sp2)–C(sp3)
bond
remains
elusive.
We
employ
kinetic
analysis,
organometallic
synthesis,
computational
investigations
to
decipher
mechanism
prototypical
Ni-catalyzed
photochemical
arylation
reaction.
Our
revise
previous
proposals,
first
by
examining
relevance
SET
EnT
processes
intermediates
relevant
HAT-based
investigation
highlights
ability
blue
light
promote
efficient
Ni–C(sp2)
homolysis
cationic
NiIII
reductive
elimination
bipyridine
NiII
complexes.
However
interesting,
rates
selectivities
these
do
not
account
productive
pathway.
Instead,
our
studies
support
involves
evolution
in
situ
generated
dihalide
intermediates,
capture
NiII(aryl)(halide)
resting
state,
key
C–C
NiIII.
Oxidative
addition
NiI,
opposed
Ni0,
rapid
NiIII/NiI
comproportionation
play
roles
process.
The
presented
herein
offer
fundamental
insight
into
reactivity
broader
catalysis.
Nature Communications,
Год журнала:
2022,
Номер
13(1)
Опубликована: Ноя. 28, 2022
Electrochemical
asymmetric
catalysis
has
emerged
as
a
sustainable
and
promising
approach
to
the
production
of
chiral
compounds
utilization
both
anode
cathode
working
electrodes
would
provide
unique
for
organic
synthesis.
However,
precise
matching
rate
electric
potential
anodic
oxidation
cathodic
reduction
make
such
idealized
electrolysis
difficult
achieve.
Herein,
cross-coupling
between
α-chloroesters
aryl
bromides
is
probed
model
reaction,
wherein
alkyl
radicals
are
generated
from
through
sequential
oxidative
electron
transfer
process
at
anode,
while
nickel
catalyst
reduced
lower
state
cathode.
Radical
clock
studies,
cyclic
voltammetry
analysis,
paramagnetic
resonance
experiments
support
synergistic
involvement
redox
events.
This
electrolytic
method
provides
an
alternative
avenue
that
could
find
significant
utility
in