Chemistry - A European Journal,
Journal Year:
2024,
Volume and Issue:
30(22)
Published: Feb. 7, 2024
Abstract
Systematic
modification
of
the
chelating
NHC‐phosphine
ligand
(NHC
=
N
‐heterocyclic
carbene)
in
highly
efficient
ketone
hydrogenation
Mn(I)
catalyst
fac
‐[(Ph
2
PCH
NHC)Mn(CO)
3
Br]
has
been
performed
and
catalytic
activity
resulting
complexes
was
evaluated
using
acetophenone
as
a
benchmark
substrate.
While
variation
phosphine
NHC
moieties
led
to
inferior
results
than
for
parent
system,
incorporation
phenyl
substituent
into
methylene
bridge
improved
performance
by
ca
.
times
providing
maximal
TON
values
range
15000–20000.
Mechanistic
investigation
combining
experimental
computational
studies
allowed
rationalize
this
beneficial
effect
an
enhanced
stabilization
reaction
intermediates
including
anionic
hydride
species
PC(Ph)NHC)Mn(CO)
H]
−
playing
crucial
role
process.
These
highlight
interest
such
carbon
substitution
strategy
being
rarely
employed
design
chemically
non‐innocent
ligands.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(26)
Published: April 21, 2023
A
homogeneous
manganese-catalyzed
cross-coupling
of
two
secondary
alcohols
for
the
divergent
synthesis
γ-disubstituted
and
β-disubstituted
ketones
is
reported.
Employing
well-defined
Mn-MACHOPh
as
catalyst,
this
novel
protocol
has
a
broad
substrate
scope
with
good
functional
group
tolerance
affords
diverse
library
valuable
disubstituted
in
moderate
to
yields.
The
strong
influence
reaction
temperature
on
selective
formation
alcohol
products
was
theorized
preliminary
DFT
studies.
Studies
have
shown
that
Gibbs
free
energy
thermodynamically
more
favourable
than
corresponding
at
lower
temperature.
Organic Chemistry Frontiers,
Journal Year:
2024,
Volume and Issue:
11(14), P. 4024 - 4040
Published: Jan. 1, 2024
This
review
provides
a
comprehensive
overview
of
metal
catalysis
in
photo-electrochemical
systems,
discussing
reaction
mechanisms
and
offering
prospects
for
this
triadic
catalytic
mode.
ChemCatChem,
Journal Year:
2024,
Volume and Issue:
16(14)
Published: March 7, 2024
Abstract
Direct
asymmetric
hydrogenation
(AH)
and
transfer
(ATH)
are
among
the
most
efficient
approaches
to
produce
chiral
building
blocks.
Recently,
these
types
of
transformations
have
witnessed
a
shift
towards
use
molecular
catalysts
based
on
earth‐abundant
transition
metals
due
their
ready
availability,
economic
advantage,
novel
properties.
With
particular
regard
manganese,
catalyst
development
has
seen
both
efficiency
substrate
scope
in
AH
ATH
greatly
improved,
with
emergence
large
number
well‐defined
Mn‐complexes
employed
this
field.
The
reaction
includes
C=O
bonds,
reduction
C=N
bonds
reductive
C=C
bonds.
Herein,
our
survey
area
focuses
catalytic
activity
such
complexes,
versatility
routes
convert
substrates
target
molecules.
We
consider
collected
findings
article
will
be
helpful
reader
by
providing
an
insight
into
ligand
design,
thereby
aiding
future
development.
Moreover,
review
is
aimed
at
highlighting
remarkable
progress
made
last
seven
years
manganese
complexes
for
enantioselective
reduction.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(2), P. 514 - 518
Published: Jan. 9, 2024
In
this
work,
we
have
constructed
three
new
Co(II)
complexes
in
which
steric
features
govern
their
structural
geometry.
The
metal
ligand-cooperation
behavior
of
the
alkoxy
arm
is
utilized
to
explore
catalytic
activities
these
with
respect
dehydrogenation.
A
wide
range
C-3-substituted
quinoline
and
quinazoline
derivatives
were
synthesized
high
yields.
developed
protocol's
usefulness
enhanced
by
chemoselective
transformation
different
fatty
alcohols
synthesize
heterocycles
having
distal
unsaturation.
Various
kinetic,
mechanistic,
control
studies
conducted
comprehend
reaction
route.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(13)
Published: Feb. 1, 2024
Abstract
The
synthesis
of
mono‐
N
‐methylated
aliphatic
primary
amines
has
traditionally
been
challenging,
requiring
noble
metal
catalysts
and
high‐pressure
H
2
for
achieving
satisfactory
yields
selectivity.
Herein,
we
developed
an
approach
the
selective
coupling
methanol
amines,
without
hydrogen,
using
a
manganese‐based
catalyst.
Remarkably,
up
to
98
%
with
broad
substrate
scope
were
achieved
at
low
catalyst
loadings.
Notably,
due
weak
base‐catalyzed
alcoholysis
formamide
intermediates,
our
novel
protocol
not
only
obviates
addition
but
also
prevents
side
secondary
‐methylation,
supported
by
control
experiments
density
functional
theory
calculations.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(20), P. 4173 - 4177
Published: May 13, 2024
Here,
we
report
the
chemoselective
hydrogenation
of
α,β-unsaturated
ketones
catalyzed
by
a
well-defined
Mn(I)
PCNHCP
pincer
complex
[(PCNHCP)Mn(CO)2H]
(1).
The
reaction
is
compatible
with
wide
variety
functional
groups
that
include
halides,
esters,
amides,
nitriles,
nitro,
alkynes,
and
alkenes,
for
most
substrates
occurs
readily
at
ambient
hydrogen
pressure
(1–2
bar).
Mechanistic
studies
deuterium
labeling
experiments
reveal
non-cooperative
mechanism,
which
further
discussed
in
this
report.
Accounts of Chemical Research,
Journal Year:
2022,
Volume and Issue:
55(18), P. 2740 - 2751
Published: Sept. 8, 2022
ConspectusThe
activation
of
weakly
polarized
bonds
represents
a
challenging,
yet
highly
valuable
process.
In
this
context,
precious
metal
catalysts
have
been
used
as
reliable
compounds
for
the
rather
inert
last
several
decades.
Nevertheless,
base-metal
complexes
including
cobalt,
iron,
or
nickel
are
currently
promising
candidates
substitution
noble
metals
in
order
to
develop
more
sustainable
processes.
past
few
years,
manganese(I)-based
were
heavily
employed
efficient
(de)hydrogenation
reactions.
However,
vast
majority
these
operate
via
metal–ligand
bifunctionality
already
well
implemented
decades
ago.
Although
high
reactivity
can
be
achieved
various
reactions,
concept
is
often
not
applicable
certain
transformations
due
outer-sphere
mechanisms.
Account,
we
outline
potential
alkylated
Mn(I)-carbonyl
nonpolar
and
moderately
polar
E–H
(E
=
H,
B,
C,
Si)
disclose
our
successful
approach
utilization
field
homogeneous
catalysis.
This
involves
rational
design
manganese
hydrogenation
reactions
involving
ketones,
nitriles,
carbon
dioxide,
alkynes.
addition
that,
reduction
alkenes
by
dihydrogen
could
series
well-defined
which
was
possible
before.
Furthermore,
elucidate
Mn-based
hydrofunctionalization
carbon–carbon
multiple
bonds.
Our
investigations
unveiled
novel
insights
into
reaction
pathways
dehydrogenative
silylation
trans-1,2-diboration
terminal
alkynes,
reported
transition
metals.
Due
catalyst
design,
under
mild
conditions.
Delightfully,
all
bench-stable
compounds.
We
took
advantage
fact
that
Mn(I)
alkyl
known
undergo
migratory
insertion
group
CO
ligand,
yielding
an
unsaturated
acyl
intermediate.
Hydrogen
atom
abstraction
ligand
then
paves
way
active
species
variety
catalytic
proceed
inner-sphere
textbook
well-known
decades,
application
still
its
infancy.
A
brief
historical
overview
manganese(I)–carbonyl
provided,
covering
synthesis
especially
iconic
stoichiometric
transformations,
e.g.,
carbonylation,
intensively
examined
Calderazzo,
Moss,
others.
An
future
applications
defined
will
given,
may
inspire
researchers
development
(base-)metal
catalysts.