Angewandte Chemie International Edition,
Journal Year:
2018,
Volume and Issue:
57(41), P. 13444 - 13448
Published: Aug. 7, 2018
Abstract
We
have
developed
unprecedented
methods
for
the
direct
transformation
of
primary
alcohols
to
alkenes
in
presence
hydrazine,
and
synthesis
mixed
by
reaction
with
hydrazones.
The
reactions
are
catalyzed
a
manganese
pincer
complex
proceed
absence
added
base
or
hydrogen
acceptors,
liberating
dihydrogen,
dinitrogen,
water
as
only
byproducts.
proposed
mechanism,
based
on
preparation
intermediates
control
experiments,
suggests
that
occurs
through
metal–ligand
cooperative
N−H
activation
hydrazone
intermediate.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(7), P. 2742 - 2747
Published: March 23, 2021
The
reduction
of
nitroarenes
to
anilines
as
well
azobenzenes
hydrazobenzenes
using
a
single
base-metal
catalyst
is
reported.
hydrogenation
reactions
are
performed
with
an
air-and
moisture-stable
manganese
and
proceed
under
relatively
mild
reaction
conditions.
transformation
tolerates
broad
range
functional
groups,
affording
aniline
derivatives
in
high
yields.
Mechanistic
studies
suggest
that
the
proceeds
via
bifunctional
activation
involving
metal–ligand
cooperative
catalysis.
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(20)
Published: March 3, 2022
The
asymmetric
hydrogenation
(AH)
of
3H-indoles
represents
an
ideal
approach
to
the
synthesis
useful
chiral
indoline
scaffolds.
However,
very
few
catalytic
systems
based
on
precious
metals
have
been
developed
realize
this
challenging
reaction.
Herein,
we
report
a
Mn-catalyzed
AH
with
excellent
yields
and
enantioselectivities.
kinetic
resolution
racemic
by
was
also
achieved
high
s-factors
construct
quaternary
stereocenters.
Many
acid-sensitive
functional
groups,
which
cannot
be
tolerated
when
using
state-of-the-art
ruthenium
catalyst,
were
compatible
manganese
catalysis.
This
new
process
expands
scope
transformation
highlights
uniqueness
earth-abundant
metal
reaction
could
proceed
catalyst
loadings
at
parts
per
million
(ppm)
level
exceptional
turnover
number
72
350.
is
highest
value
yet
reported
for
metal-catalyzed
Journal of the American Chemical Society,
Journal Year:
2022,
Volume and Issue:
144(18), P. 8129 - 8137
Published: April 27, 2022
Homogeneously
catalyzed
reactions
often
make
use
of
additives
and
promotors
that
affect
reactivity
patterns
improve
catalytic
performance.
While
the
role
reaction
is
discussed
in
view
their
chemical
reactivity,
we
demonstrate
they
can
be
involved
catalysis
indirectly.
In
particular,
adjust
thermodynamics
key
transformations
homogeneous
hydrogenation
enable
would
unfavorable
otherwise.
We
identified
this
phenomenon
a
set
well-established
new
Mn
pincer
catalysts
suffer
from
persistent
product
inhibition
ester
hydrogenation.
Although
alkoxide
base
do
not
directly
participate
inhibitory
transformations,
equilibrium
constants
these
processes.
Experimentally,
confirm
by
varying
promotor
concentration
one
control
catalyst
speciation
inflict
substantial
changes
to
standard
free
energies
steps
cycle.
Despite
fact
latter
are
universally
assumed
constant,
state
subject
external
control.
These
results
suggest
viewed
as
an
integral
component
medium,
on
its
own
capable
improving
performance
reshaping
seemingly
rigid
thermodynamic
landscape
transformation.
Journal of the American Chemical Society,
Journal Year:
2019,
Volume and Issue:
141(31), P. 12202 - 12206
Published: July 15, 2019
Amide
synthesis
is
one
of
the
most
important
transformations
in
chemistry
and
biology.
The
direct
use
ammonia
for
incorporation
nitrogen
functionalities
organic
molecules
an
attractive
environmentally
benign
method.
We
present
here
a
new
amides
by
acceptorless
dehydrogenative
coupling
benzyl
alcohols
ammonia.
reaction
catalyzed
pincer
complex
earth-abundant
manganese
presence
stoichiometric
base,
making
overall
process
economical,
efficient,
sustainable.
Interesting
mechanistic
insights
based
on
detailed
experimental
observations,
indicating
crucial
role
are
provided.
The Journal of Organic Chemistry,
Journal Year:
2019,
Volume and Issue:
84(22), P. 14627 - 14635
Published: Oct. 30, 2019
The
first
transition-metal-free
catalytic
protocol
for
controlled
reduction
of
amide
functions
using
cheap
and
bench-stable
hydrosilanes
as
reducing
agents
has
been
established.
By
altering
the
hydrosilane
solvent,
new
method
enables
selective
cleavage
unactivated
C-O
bonds
in
amides
allows
C-N
to
selectively
break
via
deacylated
cleavage.
Overall,
this
novel
process
may
offer
a
versatile
alternative
current
methodologies
employing
stoichiometric
metal
systems
carboxamides.
Dalton Transactions,
Journal Year:
2019,
Volume and Issue:
48(21), P. 7358 - 7366
Published: Jan. 1, 2019
The
synthesis
and
reactivity
of
Mn(i)
complexes
bearing
bifunctional
ligands
comprising
both
the
amine
N-H
benzimidazole
fragments
are
reported.
Among
various
ligands,
N-((1H-benzimidazol-2-yl)methyl)aniline
ligand
containing
complex
presented
higher
in
transfer
hydrogenation
(TH)
ketones
2-propanol.
Experimentally,
it
was
established
that
proton
played
a
vital
role
enhancement
catalytic
activity.
Utilizing
this
system
wide
range
aldehydes
were
reduced
efficiently.
Notably,
TH
several
imines,
as
well
chemoselective
reduction
unsaturated
ketones,
achieved
presence
catalyst.
DFT
calculations
carried
out
to
understand
plausible
reaction
mechanism
which
disclosed
followed
concerted
outer-sphere
mechanism.
Catalysts,
Journal Year:
2020,
Volume and Issue:
10(6), P. 635 - 635
Published: June 7, 2020
Recently,
an
increasing
number
of
metal
complex
catalysts
have
been
developed
to
achieve
the
activation
or
transformation
substrates
based
on
cooperation
between
atom
and
its
ligands.
In
such
“cooperative
catalysis,”
ligand
not
only
is
bound
metal,
where
it
exerts
steric
electronic
effects,
but
also
functionally
varies
structure
during
elementary
processes
catalytic
reaction.
this
review
article,
we
focus
metal–ligand
involving
aromatization
dearomatization
ligand,
thus
introducing
newest
developments
examples
homogeneous
reactions.
Organic Chemistry Frontiers,
Journal Year:
2019,
Volume and Issue:
6(19), P. 3420 - 3427
Published: Jan. 1, 2019
Modified
poly
2,4-dichlorostyrene
microspheres
were
designed
and
synthesized,
proved
to
be
an
effective
carrier
synthesize
supported
manganese
dioxide
nanoparticles.
