This
study
describes
the
synthesis
of
palladium
nanoparticles
stabilized
from
tea
extracts
supported
on
magnetic
and
named
as
ION-SiO2/TE-Pd(0).
In
this
respect,
while
our
is
one
limited
number
studies
reported
for
catalytic
denitrogenative
coupling
arylbromide
arylhydrazine.
lead
to
construction
important
substituted
biaryls
easily
accessible
bromoarenes
bearing
various
substituents
with
82-92%
yields.
The
synthesized
nanocatalyst
were
characterized
using
structural
morphological
characterization
techniques.
It
was
also
observed
that
ION-SiO2/TE-Pd(0)
catalyst
had
good
activity
even
after
six
cycles.
Chinese Journal of Chemistry,
Год журнала:
2022,
Номер
41(9), С. 1099 - 1118
Опубликована: Дек. 13, 2022
Comprehensive
Summary
Sonogashira
cross‐coupling
protocol,
typically
showing
the
reaction
between
aryl/vinyl
halide
and
terminal
alkyne,
has
been
a
widely
used
protocol
for
constructing
C(sp
2
)‐C(sp)
bond.
The
resulting
internal
alkynes
are
highly
versatile
reaching
differently
functionalized
alkyne‐containing
scaffolds
or
serving
as
valuable
synthetic
synthons
to
many
other
functional
groups.
It
is
worth
noting
that
products
originated
from
this
coupling
mostly
applicable
be
transformed
into
corresponding
Z
‐alkene,
alkane,
heterocyclic
moieties
in
natural
product
syntheses.
conditions
catalyst
systems
able
tweaked
order
facilitate
activation
of
steric
hindered
and/or
electron‐rich
electrophiles.
Pd‐catalyzed
copper‐free
caught
increasing
attention
improved
method
can
more
environmentally
friendly.
What
more,
readily
amended
allow
fusion
carbonylation
decarboxylation
step
catalytic
cycle,
thus
complex
yet
convergent
synthesis
proceed
an
operationally
simple
one‐pot
manner.
Catalysis Communications,
Год журнала:
2024,
Номер
187, С. 106862 - 106862
Опубликована: Фев. 1, 2024
Novel
palladium
based
magnetic
nanocatalyst
was
synthesized
by
the
co-precipitation
method
and
coated
with
silica
tea
extract
as
stabilizing
agent.
Palladation
onto
prepared
nanocomposite
done
to
get
ION-SiO2/TE-Pd(0)
catalyst.
Our
study
is
one
of
limited
number
studies
reported
for
catalytic
denitrogenative
coupling
arylbromide
arylhydrazine.
This
led
construction
important
substituted
biaryls
bearing
various
substituents
82–92%
yields.
The
characterized
using
structural
morphological
characterization
techniques.
It
also
observed
that
only
2
mol%
catalyst
sufficient
catalysis
reusable
upto
six
cycles.
Organic Letters,
Год журнала:
2023,
Номер
25(17), С. 2975 - 2980
Опубликована: Апрель 20, 2023
We
report
the
first
Suzuki-Miyaura
cross-coupling
of
2-pyridyl
ammonium
salts
by
highly
selective
N-C
activation
catalyzed
air-
and
moisture-stable
Pd(II)-NHC
(NHC
=
N-heterocyclic
carbene)
precatalysts.
The
use
well-defined
reactive
[Pd(IPr)(3-CF3-An)Cl2]
(An
aniline)
or
[Pd(IPr)(cin)Cl]
(cin
cinnamyl)
catalysts
permits
an
exceptionally
broad
scope
to
furnish
valuable
biaryl
heterobiarylpyridines
that
are
ubiquitous
in
medicinal
chemistry
agrochemistry
research.
overall
process
leverages
Chichibabin
C-H
amination
pyridines
with
enable
attractive
strategy
problem.
utility
method
discovery
potent
agrochemicals
is
presented.
Considering
importance
2-pyridines
versatility
methods,
we
envision
this
new
C-H/N-C
will
find
application.
Inorganic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(16), С. 4974 - 5003
Опубликована: Янв. 1, 2024
This
review
highlights
the
factors
that
can
dictate
properties
of
cluster-based
catalysts
towards
coupling
reactions,
such
as
ligand
effect,
doping
support
and
defective
effect.
ACS Catalysis,
Год журнала:
2022,
Номер
12(24), С. 15323 - 15333
Опубликована: Ноя. 30, 2022
In
the
last
15
years,
copper-catalyzed
borylative
transformations
utilizing
boryl–copper
have
been
established
as
a
powerful
activation
mode
in
organic
synthesis
and
catalysis,
enabling
direct
of
various
π-systems.
Although
many
these
use
NHC
(N-heterocyclic
carbene)
ligands,
studies
almost
exclusively
limited
to
derivatives
imidazol-2-ylidenes.
However,
molecular
properties
N-aryl-imidazol-2-ylidenes,
such
IPr
(IPr
=
1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene),
are
by
(1)
high
degree
heteroatom
stabilization
(2)
symmetrical
substitution
nitrogen
atoms.
Herein,
we
report
study
on
Cu(I)–thiazol-2-ylidenes,
thiazole
analogues
imidazol-2-ylidenes,
which
feature
distinct
half-umbrella
shape
coordinating
ligand
exhibit
lower
ancillary
through
reduced
π-donation
from
sulfur.
We
present
development
family
stable
where
combined
sterics
thiazol-2-ylidenes
lead
monomers
[Cu(NHC)X]
or
bridged-halo
dimers
[Cu(NHC)
(μ-X)]2,
their
crystallographic
characteristics,
application
hydroboration
alkynes
afford
trisubstituted
vinylboronates
β-hydroboration
internal
terminal
alkynes.
Application
late-stage
modification
detailed
mechanistic
catalyst
structure
presented.
Most
crucially,
Cu(I)–thiazol-2-ylidenes
show
much
higher
β-selectivity
than
that
classical
affording
vinylborons
excellent
yields
at
ambient
conditions.
The
unique
"half-umbrella"
reverses
α/β
regioselectivity
observed
with
imidazol-2-ylidenes
Kinetic
demonstrate
supersede
Considering
significant
utility
π-systems,
anticipate
will
advance
synthetic
catalysis.
Dalton Transactions,
Год журнала:
2023,
Номер
52(13), С. 4122 - 4135
Опубликована: Янв. 1, 2023
Pd/NHC
complexes
(NHCs
-
N-heterocyclic
carbenes)
with
electron-withdrawing
halogen
groups
were
prepared
by
developing
an
optimized
synthetic
procedure
to
access
imidazolium
salts
and
the
corresponding
metal
complexes.
Structural
X-ray
analysis
computational
studies
have
been
carried
out
evaluate
effect
of
CF3
substituents
on
Pd-NHC
bond
provided
insight
into
possible
electronic
effects
molecular
structure.
The
introduction
changes
ratio
σ-/π-contributions
but
does
not
affect
energy.
Here,
we
report
first
approach
a
comprehensive
range
o-,
m-,
p-XC6H4-substituted
NHC
ligands,
including
incorporation
Pd
(X
=
F,
Cl,
Br,
CF3).
catalytic
activity
obtained
was
compared
in
Mizoroki-Heck
reaction.
For
substitution
atoms,
following
relative
trend
observed:
X
Br
>
F
for
all
changed
order:
m-X,
p-X
o-X.
Evaluation
showed
significant
increase
catalyst
performance
case
unsubstituted
complex.
Bulletin of the Chemical Society of Japan,
Год журнала:
2023,
Номер
96(3), С. 303 - 305
Опубликована: Фев. 24, 2023
Abstract
Alkenylammonium
salts
are
a
unique
class
of
compounds,
wherein
an
electron-withdrawing
ammonio
group
is
attached
to
olefin.
Although
these
structurally
simple,
the
synthesis
α-substituted
alkenylammonium
has
been
sparsely
explored.
Herein
we
report
α-aryl
and
α-alkynylated
through
Suzuki–Miyaura
Sonogashira
coupling.
