Abstract
The
photocatalytic
conversion
of
lignin
into
value‐added
chemicals
especially
those
functionalized
molecules
represent
one
the
most
important
strategies
for
sustainable
and
environmental‐friendly
development.
Cleavage
C−C
bonds
in
under
mild
conditions
refining
useful
is
meaningful
but
challenging.
Meanwhile,
assembly
diverse
functional
groups
active
fragments
during
depolymerization
great
Herein,
using
cheap
iron
catalysts
visible
light
irradiation,
highly
selective
efficient
cleavage
C
α
−C
β
bond
realized
via
ligand‐to‐metal
charge
transfer
(LMCT)
hydrogen
atom
(HAT)
processes.
subsequent
divergent
functionalization
generated
fragment‐based
radical
intermediates
enables
an
formation
molecules.
This
method
also
effective
native
lignin,
yielding
two
identified
benzaldehyde
monomers
a
total
yield
8.7
wt
%.
Advanced Synthesis & Catalysis,
Год журнала:
2024,
Номер
366(7), С. 1595 - 1605
Опубликована: Фев. 3, 2024
Abstract
Herein,
we
present
a
photoinduced
deconstructive
alkoxyamination
of
alkyl
alcohols
catalyzed
by
iron
salts.
This
transformation
involves
the
initiation
alkoxy
radicals
through
chlorine
radical‐induced
radical
formation,
followed
β
‐scission
and
trapping
resulting
carbon
with
2,2,6,6‐tetramethylpiperidin‐1‐yl
(TEMPO).
reaction
exhibits
broad
substrate
scope
(40
examples),
including
primary
secondary
that
are
prone
to
oxidation
combination
TEMPO
iron.
Mechanistic
investigations
have
revealed
enhanced
coordination
chloride
ion
center
inhibits
OH
process,
thereby
enabling
tolerance
alcohols.
Green Chemistry,
Год журнала:
2024,
Номер
26(14), С. 8161 - 8203
Опубликована: Янв. 1, 2024
The
strategic
installation
of
the
“magic
methyl”
group
has
become
highly
desirable
for
drug
discovery.
This
review
summarized
recent
photochemical
and
electrochemical
strategies
in
installing
methyl
group.
Advanced Synthesis & Catalysis,
Год журнала:
2023,
Номер
365(7), С. 1072 - 1081
Опубликована: Март 17, 2023
Abstract
Being
in
its
infancy,
radical
cross‐coupling
is
highly
efficient
for
C−C
bond
construction,
though
suffers
from
selectivity
problems
and
limited
reaction
types.
New
methodologies
to
realize
selectively
are
desired.
Herein,
an
iron
catalyzed
deconstructive
cyanomethylation
of
unstrained
cyclic
linear
alcohols
with
acetonitrile
has
been
developed
through
cross‐coupling.
The
unprecedented
method
enables
a
ring‐opening
functionalization
cyclohexanols
produce
α‐cyanomethyl
ketones.
Notably,
the
challenging
involves
twice
single
cleavage
β‐scission
alkoxyl
intermediates,
C(
sp
3
)−H
transformation
via
hydrogen
atom
transfer
(HAT)
procedures,
resulting
two
carbon
species
that
process
form
new
)−C(
)
selectively.
α‐arylketo
α‐aryl
substituted
tertiary
can
also
be
applied
as
substrates,
leading
terminal
cyano‐functionalized
products,
ketone
leaving
fragment.
Mechanistically,
procedure
generate
chlorine
in‐situ
formed
intermediate
cycloalkyl
hypochlorite
was
suggested.
magnified
image
Chinese Journal of Organic Chemistry,
Год журнала:
2023,
Номер
43(4), С. 1386 - 1386
Опубликована: Янв. 1, 2023
In
recent
years,
the
development
and
application
of
transition
metal
ruthenium
or
iridium
complexes
based
photocatalysts
have
opened
up
a
new
research
field
for
organic
synthesis,
which
provides
mild
efficient
strategies
construction
chemical
bonds
transformations.In
order
to
enrich
types
photocatalysts,
broaden
scope
photocatalysis,
develop
green
sustainable
chemistry,
some
low-cost
easily
available
organometallic
with
copper
iron
were
applied
as
recently.Iron-complexes
feature
non-toxicity,
rich
variety,
unique
property
charge
transfer
from
ligands
metals,
enable
them
show
extraordinary
capability
in
photocatalytic
synthesis.According
different
reaction
types,
this
review
focuses
on
photoinduced
iron-catalysis
synthesis
including
C-H
bond
functionalization,
C-C
bifunctionalization
alkenes,
cross-coupling
reaction,
decarboxylative
selective
oxidation
reduction.
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(26), С. 5382 - 5386
Опубликована: Янв. 1, 2023
This
paper
describes
the
iron-catalyzed
photochemical
carbonylation
of
benzylic
C-H
bonds
resulting
in
synthesis
various
aryl
ketones.
Using
5
W
blue
LED
irradiation,
reactions
proceed
smoothly
presence
2
mol%
FeBr3
MeOH
at
35
°C.
The
catalytic
system
could
be
extended
for
oxidation
silane,
thioether,
and
phosphine
into
silenol,
sulphoxide,
phosphoxide,
respectively.
A
mechanistic
study
suggests
that
a
hydrogen
bond-stabilized
iron-hydroperoxo
species
is
reactive
intermediate.
It
shown
reaction
proceeds
via
four-electron-transfer
pathway,
cation
seems
to
crucial
species.
method
applied
pomalyst,
haloperidol,
melperone,
lenperone.
ACS Catalysis,
Год журнала:
2023,
Номер
14(1), С. 585 - 593
Опубликована: Дек. 26, 2023
An
efficient
metal-free
photocatalytic
method
for
the
alkylation
of
alkenes
using
accessible
aliphatic
alcohols
as
redox
auxiliaries
is
presented.
C-centered
radicals
can
be
generated
under
mild
conditions
and
subsequently
employed
in
a
C(sp3)–C(sp3)
bond-forming
process,
which
overall
provides
C1
tethering
strategy
nucleophiles
electrophiles.
The
optimized
accommodate
various
electron-deficient
secondary/tertiary
alcohols,
with
applications
late-stage
functionalization
natural
products
pharmaceutically
relevant
compounds.
Mechanistic
investigations
revealed
complex
mechanistic
manifold,
including
non-PCET
fragmentation
concerted/stepwise
PCET.
Even
though
previously
thought
PCET
type
mechanism
compatible
our
observations,
most
probably
constitutes
main
pathway.
