Chemical Science,
Год журнала:
2024,
Номер
unknown
Опубликована: Янв. 1, 2024
Selectively
customizing
hydrogenation
products
of
urea
derivatives
or
carbamates
without
external
acid/base
additives
remains
unrealized.
Herein,
we
report
a
promising
route
to
selectively
obtain
formamides,
methanol,
methylamines.
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.
ACS Sustainable Chemistry & Engineering,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 2, 2025
The
preparation
of
methyl-substituted
amines
by
direct
N-methylation
with
CO2/H2
is
an
important
reaction
for
CO2
utilization
and
organic
synthesis.
However,
the
design
construction
effective
stable
non-noble-metal
catalysts
this
remain
challenging.
Here,
a
cheap
non-noble-Cu-based
catalyst
was
prepared
applied
in
N-methylaniline
H2.
5%Cu-ZnO(3.75%)/TiO2
showed
98.8%
yield
initial
TOF
7.7
h–1
after
24
h
under
453
K,
1.5
MPa
CO2,
4.5
H2,
which
superior
to
5%Cu/TiO2,
5%Cu/ZnO,
reported
Cu-based
catalysts.
Furthermore,
can
be
reused
at
least
four
times
various
excellent
selectivity.
characterizations
experimental
results
that
Cu0
active
site,
exhibited
largest
surface
amount,
thereby
contributing
catalytic
performance.
mechanism
H2
proposed
based
on
spectroscopic
studies,
kinetic
control
experiments.
proceeded
HCHO
N-methylformanilide
intermediates,
formation
from
rate-determining
step.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(37), С. 25562 - 25568
Опубликована: Авг. 8, 2024
The
development
of
methods
for
the
chemical
recycling
polyurethanes
is
recognized
as
an
urgent
issue.
Herein,
we
report
Ir-catalyzed
hydrogenolysis
urethane
C–O
bond
to
produce
formamides
and
alcohols,
where
both
ester
amide
functionalities
are
tolerated.
chemoselectivity
observed
counterintuitive
generally
accepted
electrophilicity
order
carbonyl
compounds.
Hydrogenolysis
urea
isocyanurate,
potential
byproducts
in
polycondensation
process
polyurethanes,
also
achieved
alongside
selective
degradation
themselves,
which
affords
diformamides
diols.
time-course
hydrogenative
polyurethane
reveals
that
cleavage
occurs
not
from
terminal,
but
any
part
polymer
chain.
present
catalysis
offers
a
novel
method
polyurethane-containing
waste.
Organometallics,
Год журнала:
2024,
Номер
43(9), С. 924 - 928
Опубликована: Апрель 18, 2024
Hydrogenolysis
of
less
reactive
carbonyl
compounds
such
as
urethanes
and
ureas
is
a
challenging
but
promising
transformation
to
utilize
new
chemical
feedstocks,
plastic
waste
carbon
dioxide
fixation
products.
In
these
transformations,
pincer-type
complexes
consisting
Ru
Mn
have
been
intensively
investigated
catalyst
design
with
bidentate
ligand
systems
has
rarely
explored.
We
report
here
the
synthesis
complex
supported
by
PN
phosphino
pyrrolido
coordination
sites,
molecular
structure
which
fully
characterized.
The
catalyzed
hydrogenolysis
ureas.
case
1,3-diphenylurea,
formanilide
was
obtained
product.
addition,
present
did
not
promote
hydrogenation
carboxamides,
showing
unique
reactivity
that
preferentially
reduces
over
in
contrast
general
order
compounds.
Organic Chemistry Frontiers,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
A
practical
approach
is
presented
for
the
highly
selective
hydrogenation
of
various
unsaturated
compounds
using
a
cutting-edge
Ru/PNN
catalytic
system,
resulting
in
high
turnover
numbers
and
substantial
production
valuable
pharmaceuticals.
Molecular Catalysis,
Год журнала:
2024,
Номер
556, С. 113923 - 113923
Опубликована: Фев. 14, 2024
A
comprehensive
computational
study
is
reported
here
on
the
mechanism
of
reaction
through
which
a
Mn(I)
pincer
catalyst
able
to
assist
hydrogenation
process
carbamate
and
urea
derivatives,
chosen
as
representative
linker
units
polyurethanes.
Four
substrate
models,
have
been
examined
in
order
evaluate
their
influence
polyurethanes
generate
useful
alcohols
amines
organic
building
blocks.
The
outcomes
exploration
highlight
different
behavior
assisting
or
carbamide
derivatives
steps
whole
mechanism.
Indeed,
for
first
step,
viability
ligand-assisted
has
found
only
involves
reversible
structural
change
ligand
that
can
partially
detach
from
metal
favor
coordination
molecule
be
processed.
instead,
go
formation
an
intermediate
interacts
with
complex
without
binding.
second
common
all
cases
requires
exploitation
hemilabile
nature
PNN
ligand.
From
calculated
energies
put
into
play
it
clearly
appears
great
ability
catalyzing
both
derivatives.