Synthesis,
Год журнала:
2023,
Номер
56(03), С. 496 - 506
Опубликована: Сен. 27, 2023
Abstract
A
photo-induced
intramolecular
electrophilic
aromatic
substitution
(SEAr)
of
N-acyloxyamides
using
FeCl3
in
1,4-dioxane
is
reported
for
the
synthesis
biologically
interesting
benzoxazin-3(4H)-ones.
It
believed
that
irradiation
with
a
blue
LED
facilitates
reaction,
serving
as
source
energy.
The
SEAr
reaction
pathway
ascribed
to
electronic
effects
present
aryl
ring
substrates.
also
applicable
useful
scaffolds
possessing
quinolin-2-one
core,
such
an
anticancer
reagent
and
analogues
brexipiprazole
cilostamide.
Green Chemistry,
Год журнала:
2023,
Номер
25(10), С. 3909 - 3915
Опубликована: Янв. 1, 2023
Visible
light-induced
highly
efficient
synthesis
of
1,3-disubstituted
bicyclo[1.1.1]pentane
with
mild
conditions,
high
atom
economy,
and
superior
functional
group
tolerance.
Reported
herein
is
a
visible-light-promoted
strategy
for
the
α-C(sp3)–H
amidation
of
cyclic
ethers
using
N-acyloxyamide
as
an
oxidative
amidating
reagent.
This
transformation
provides
straightforward
approach
to
various
α-amidated
under
metal-
and
additive-free
conditions.
The
synthetic
utility
products
was
demonstrated
through
facile
transformations,
including
reduction,
allylation,
acylation,
sulfonamidation,
gram-scale
reactions.
Preliminary
mechanistic
studies
suggest
radical/radical
cross-coupling
process,
with
C(sp3)–H
bond
cleavage
identified
rate-determining
step.
Abstract
Iron‐catalyzed
C−H
amination
is
emerging
as
an
attractive
and
sustainable
method
to
install
amine
functionalities
into
organic
compounds.
Amination
of
C(
sp
3
)−H
bonds
usually
mediated
by
iron‐nitrene
intermediate
via
a
Hydrogen
Atom
Abstraction/Radical
Recombination
mechanism
reminiscent
biomimetic
oxidation.
Accordingly,
this
transformation
can
be
catalyzed
engineered
iron
enzymes,
heme
nonheme
complexes
well
salts,
although
it
often
limited
intramolecular
reactions
and/or
activated
positions.
Aromatic
2
addition
electrophilic
nitrenes
or
protonated
N‐radical
intermediates
(produced
with
Fe
catalysts)
aromatic
systems.
Again,
high
selectivity
obtained
(pseudo)
reactions.
From
mechanistic
perspective,
several
nitrene
have
been
isolated
characterized
over
the
years
in
different
ligand
scaffolds
oxidation
states.
Structure‐activity
correlations
drawn
only
few
cases
point
key
role
spin
density
on
state.
This
review
describes
state
art
for
homogeneous
focusing
last
5
(2019–2023)
from
mechanism‐driven
catalyst
design
perspective.
ACS Catalysis,
Год журнала:
2023,
Номер
13(7), С. 4552 - 4559
Опубликована: Март 21, 2023
C–H
functionalization
reactions
catalyzed
by
iron,
the
most
abundant
transition
metallic
element
in
Earth's
crust,
are
one
of
ideal
synthetic
methods.
However,
there
a
limited
number
strategies
for
iron-catalyzed
directed
activation
when
compared
to
other
first-row
metals.
Here,
we
report
iron/photosensitizer-catalyzed
alkenylation
amide
derivatives
via
σ-CAM
(σ-complex-assisted
metathesis)
promoted
situ
generation
an
iron
metallacycle.
Mechanistic
experiments
suggest
that
bond
cleavage
would
proceed
from
metallacycle
generated
rather
than
oxidative
addition
low-valent
species.
Organic Letters,
Год журнала:
2023,
Номер
25(13), С. 2300 - 2305
Опубликована: Март 27, 2023
Here
we
report
facile
and
manipulable
access
to
methylenebisamide
derivatives
via
visible-light-driven
radical
cascade
processes
incorporating
C(sp3)–H
activation
C–N/N–O
cleavage.
Mechanistic
studies
reveal
that
a
traditional
Ir-catalyzed
photoredox
pathway
novel
copper-induced
complex-photolysis
are
both
involved,
contributing
activating
the
inert
N-methoxyamides
rendering
valuable
bisamides.
This
approach
exhibits
many
advantages,
including
mild
reaction
conditions,
broad
scope
functional
group
tolerance,
competitive
step
economy.
Given
mechanistic
plenitude
operational
simplicity,
believe
this
package
deal
paves
promising
way
for
synthesis
of
nitrogen-containing
molecules.
Chemical Communications,
Год журнала:
2023,
Номер
59(40), С. 6056 - 6059
Опубликована: Янв. 1, 2023
Herein,
we
report
a
catalyst-free
synthesis
of
C3-halo
substituted
bicyclo[1.1.1]pentylamines
under
mild
conditions.
The
reaction
involves
the
use
sodium
hypohalites
and
sulfonamides
to
generate
N-halosulfonamides
in
situ,
which
subsequently
undergo
radical
addition
with
[1.1.1]propellane
yield
desired
products
suitable
functional
group
tolerance.
