Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(3), P. 1753 - 1759
Published: Jan. 9, 2024
Herein,
we
report
the
direct
carboxylation
of
unactivated
secondary
alkyl
bromides
enabled
by
merger
photoredox
and
nickel
catalysis,
a
previously
inaccessible
endeavor
in
arena.
Site-selectivity
is
dictated
kinetically
controlled
insertion
CO2
at
initial
C(sp3)–Br
site
rapid
formation
Ni(I)–alkyl
species,
thus
avoiding
undesired
β-hydride
elimination
chain-walking
processes.
Preliminary
mechanistic
experiments
reveal
subtleties
stereoelectronic
effects
for
guiding
reactivity
site-selectivity.
Angewandte Chemie International Edition,
Journal Year:
2020,
Volume and Issue:
59(48), P. 21530 - 21534
Published: Aug. 28, 2020
Abstract
A
highly
enantio‐
and
regioselective
hydroarylation
process
of
vinylarenes
with
aryl
halides
has
been
developed
using
a
NiH
catalyst
new
chiral
bis
imidazoline
ligand.
broad
range
structurally
diverse,
enantioenriched
1,1‐diarylalkanes,
structure
found
in
number
biologically
active
molecules,
have
obtained
excellent
yields
enantioselectivities
under
extremely
mild
conditions.
Angewandte Chemie International Edition,
Journal Year:
2020,
Volume and Issue:
59(13), P. 5398 - 5402
Published: Jan. 17, 2020
We
report
a
NiH-catalyzed
migratory
defluorinative
coupling
between
two
electronically
differentiated
olefins.
A
broad
range
of
unactivated
donor
olefins
can
be
joined
directly
to
acceptor
containing
an
electron-deficient
trifluoromethyl
substituent
in
both
intra-
and
intermolecular
fashion
form
gem-difluoroalkenes.
This
shows
site-
chemoselectivity
under
mild
conditions,
with
the
formation
tertiary
or
quaternary
carbon
center.
Angewandte Chemie International Edition,
Journal Year:
2019,
Volume and Issue:
58(51), P. 18519 - 18523
Published: Oct. 23, 2019
Abstract
Nickel
hydride
(NiH)
catalyzed
hydrocarbonation
has
emerged
as
an
efficient
approach
to
construct
new
C−C
bonds
containing
at
least
one
C(sp
3
)
center.
However,
the
regioselectivity
of
this
reaction
is
by
far
dictated
substrates.
Described
here
a
strategy
achieve
two
different
regioselectivites
hydroalkylation
same
substrates
using
ligand
control.
This
enables
first
regiodivergent
3‐pyrrolines,
yielding
both
2‐
and
3‐alkylated
pyrrolidines,
valuable
synthetic
intermediates
common
motifs
in
many
bioactive
molecules.
method
demonstrates
broad
scope
high
functional‐group
tolerance,
can
be
applied
late‐stage
functionalizations.
Angewandte Chemie International Edition,
Journal Year:
2020,
Volume and Issue:
59(48), P. 21436 - 21441
Published: Aug. 12, 2020
Abstract
Metal‐catalyzed
chain‐walking
reactions
have
recently
emerged
as
a
powerful
strategy
to
functionalize
remote
positions
in
organic
molecules.
However,
protocol
for
nonconjugated
dienes
remains
scarcely
reported,
and
developments
are
currently
ongoing.
In
this
Communication,
nickel‐catalyzed
asymmetric
hydrocyanation
of
involving
process
is
demonstrated.
The
reaction
exhibits
excellent
regio‐
chemoselectivity,
wide
range
substrates
were
tolerated,
delivering
the
products
high
yields
enantioselectivities.
Deuterium‐labeling
experiments
support
process,
which
involves
an
iterative
β‐H
elimination
reinsertion
processes.
Gram‐scale
synthesis,
regioconvergent
experiments,
downstream
transformations
gave
further
insights
into
potential
transformation.
Journal of the American Chemical Society,
Journal Year:
2021,
Volume and Issue:
143(35), P. 14089 - 14096
Published: Aug. 26, 2021
A
nickel-catalyzed,
multicomponent
regio-
and
enantioselective
coupling
via
sequential
hydroformylation
carbonylation
from
readily
available
starting
materials
has
been
developed.
This
modular
hydrofunctionalization
strategy
enables
the
straightforward
reductive
hydrocarbonylation
of
a
broad
range
unactivated
alkenes
to
produce
wide
variety
unsymmetrical
dialkyl
ketones
bearing
functionalized
α-stereocenter,
including
enantioenriched
chiral
α-aryl
α-amino
ketones.
It
uses
bisoxazoline
as
ligand,
silane
reductant,
chloroformate
safe
CO
source,
racemic
secondary
benzyl
chloride
or
an
N-hydroxyphthalimide
(NHP)
ester
protected
acid
alkylation
reagent.
The
benign
nature
this
process
renders
method
suitable
for
late-stage
functionalization
complex
molecules.
Nature Communications,
Journal Year:
2020,
Volume and Issue:
11(1)
Published: Sept. 25, 2020
Abstract
Despite
remarkable
recent
advances
in
transition-metal-catalyzed
C(sp
3
)−C
cross-coupling
reactions,
there
remain
challenging
bond
formations.
One
class
of
such
reactions
include
the
formation
tertiary
-C(sp
bonds,
presumably
due
to
unfavorable
steric
interactions
and
competing
isomerizations
alkyl
metal
intermediates.
Reported
herein
is
a
Ni-catalyzed
migratory
3,3-difluoroallylation
unactivated
bromides
at
remote
centers.
This
approach
enables
facile
construction
otherwise
difficult
prepare
all-carbon
quaternary
Key
success
this
transformation
an
unusual
functionalization
via
chain
walking
most
sterically
hindered
)
center
substrate.
Preliminary
mechanistic
radical
trapping
studies
with
primary
suggest
unique
mode
C-radical
generation
through
chain-walking
followed
by
Ni–C
homolysis.
strategy
complementary
existing
coupling
protocols
tert
-alkyl
organometallic
or
halide
reagents,
it
expedient
centers
from
easily
available
starting
materials.
Angewandte Chemie International Edition,
Journal Year:
2020,
Volume and Issue:
59(23), P. 9186 - 9191
Published: March 6, 2020
Abstract
A
redox‐relay
migratory
hydroarylation
of
isomeric
mixtures
olefins
with
arylboronic
acids
catalyzed
by
nickel
complexes
bearing
diamine
ligands
is
described.
range
structurally
diverse
1,1‐diarylalkanes,
including
those
containing
a
1,1‐diarylated
quaternary
carbon,
were
obtained
in
excellent
yields
and
high
regioselectivity.
Preliminary
experimental
evidence
supports
the
proposed
non‐dissociated
chainwalking
aryl‐nickel(II)‐hydride
species
along
alkyl
chain
alkenes
before
selective
reductive
elimination
at
benzylic
position.
catalyst
loading
as
low
0.5
mol
%
proved
to
be
sufficient
large‐scale
synthesis
while
retaining
reactivity,
highlighting
practical
value
this
transformation.
Chinese Journal of Chemistry,
Journal Year:
2021,
Volume and Issue:
40(5), P. 651 - 661
Published: Dec. 3, 2021
Comprehensive
Summary
Enantioselective
NiH‐catalyzed
reductive
hydrofunctionalization
of
olefins
has
attracted
much
attention
in
recent
years.
Using
simple
chiral
ligands,
a
wide
array
functionalized
and
electrophiles
can
undergo
diverse
transformations
to
afford
hydrofunctionalized
products,
regio‐
enantioselectively.
These
processes
avoid
the
prior
preparation
organometallic
reagents,
construct
stereogenic
center
at
carbon
originating
either
from
olefin
or
electrophile.
This
review
discusses
background,
major
progress
mechanistic
investigations
this
reaction.
Nature Communications,
Journal Year:
2020,
Volume and Issue:
11(1)
Published: Feb. 7, 2020
Abstract
Double
hydroboration
of
dienes
is
the
addition
a
hydrogen
and
boryl
group
to
two
double
bonds
diene
molecule
represents
straightforward
effective
protocol
prepare
synthetically
versatile
bis(boryl)alkanes,
provided
that
this
reaction
occurs
selectively.
However,
can
potentially
yield
several
isomeric
organoboron
products,
it
still
remains
challenge
control
regioselectivity
reaction,
which
allows
selective
production
single
product,
in
particular,
for
broad
scope
dienes.
By
employing
readily
available
cobalt
catalyst,
here
we
show
yields
useful
gem
-bis(boryl)alkanes
with
excellent
regioselectivity.
In
addition,
encompasses
wide
range
conjugated
non-conjugated
Furthermore,
mechanistic
studies
indicate
cobalt-catalyzed
through
boryl-directed
chain-walking
alkenylboronates
generated
from
anti
-Markovnikov
1,2-hydroboration
1,n-diene.
