Amination of Aminopyridines via η6-Coordination Catalysis
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(33), С. 22906 - 22912
Опубликована: Авг. 9, 2024
Pyridine,
a
widespread
aromatic
heterocycle,
features
sp
Язык: Английский
C–H functionalization through benzylic deprotonation with π-coordination or cation–π-interactions
Chemical Society Reviews,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
Transition-metals
bind
arene
π-systems,
removing
e
−
density
and
acidifying
benzylic
C–H’s.
Main
group
metals
achieve
this
via
cation–π
interactions.
Both
interactions
enable
catalytic
base-promoted
selective
C–H
functionalization.
Язык: Английский
Photoredox-Catalyzed Nucleophilic Aromatic Substitution of Halophenols with Azoles via Oligomeric Phenylene Oxide Radicals
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 6, 2025
Nucleophilic
aromatic
substitution
(SNAr)
reactions
are
widely
employed
in
organic
synthesis
yet
typically
require
the
use
of
electron-deficient
arenes
for
efficient
reactivity.
Herein,
we
report
a
photocatalytic
protocol
formal
SNAr
electron-rich
4-halophenols
with
azole
nucleophiles
under
mild,
redox-neutral
conditions.
The
transformation
proceeds
via
two-stage
mechanism
consisting
initial
halophenol
oligomerization
to
produce
key
oligo(phenylene
oxide)
intermediate
and
its
subsequent
breakdown
through
enabled
by
photoredox-catalyzed
arene
umpolung.
Reaction
monitoring,
stoichiometric
control
experiments,
luminescence
quenching
data
implicate
phenoxyl
radicals
Brønsted
acid-activated
as
reactive
species
stages,
respectively.
synthetic
utility
this
method
is
demonstrated
across
17
(pseudo)halophenols
bearing
variety
leaving
groups
(F,
Cl,
Br,
OMs,
OTs)
22
examples.
Язык: Английский
Arene and Heteroarene Functionalization Enabled by Organic Photoredox Catalysis
Accounts of Chemical Research,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 12, 2025
ConspectusAromatic
functionalization
reactions
are
some
of
the
most
fundamental
transformations
in
organic
chemistry
and
have
been
a
mainstay
chemical
synthesis
for
over
century.
Reactions
such
as
electrophilic
nucleophilic
aromatic
substitution
(EAS
SNAr,
respectively)
represent
two
reaction
classes
arene
elaboration
still
today
typify
utilized
methods
functionalization.
Despite
reliable
reactivity
accessed
by
these
venerable
transformations,
space
that
can
be
EAS
SNAr
is
inherently
limited
due
to
electronic
requirements
substrate.
In
case
EAS,
highly
active
electrophiles
paired
with
electron-neutral
electron-rich
(hetero)arenes.
For
electron-deficient
(hetero)arenes
possess
appropriate
nucleofuges
(halides,
-NO2,
etc.)
required
reactivity.
The
inherent
limitations
on
(hetero)arene
presented
an
opportunity
develop
alternative
access
increased
expand
arsenal
available
synthetic
chemists.For
past
decade,
our
research
has
concentrated
developing
novel
functionalization,
particular
focus
arenes
applying
late-stage
Specifically,
undergo
single
electron
oxidation
photoredox
catalyst
under
irradiation,
forming
cation
radicals.
These
radicals
act
key
intermediates
various
transformations.
While
typically
unreactive
toward
nucleophiles,
reactive
capable
engaging
common
nucleophiles.This
Account
details
dichotomy
via
radicals:
C-H
nucleophiles
aerobic
conditions
or
radical
accelerated
(CRA-SNAr)
anaerobic
settings.
Based
experimental
computational
studies,
we
propose
reversible
addition
occur
at
ipso-,
para-,
ortho-positions
relative
electron-releasing
group.
Under
conditions,
formed
para-
ortho-addition
additional
irreversible
step,
resulting
major
outcome.
Conversely,
absence
external
oxidant,
not
observed,
ipso-addition
predominates,
releasing
alcohol
HF
nucleofuge,
leading
products.
Building
success
also
explored
their
applications
positron
emission
tomography
(PET)
radiotracer
development.
Both
18F-
11CN-
applied
radiofluorination
radiocyanation
arenes,
respectively.
Applications
radiotracers
synthesized
demonstrated
preclinical
clinical
models.
Язык: Английский
Visible-Light Induced Etherification of C(sp3)–H Bonds with Phenols
Organic Letters,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 3, 2025
The
visible-light
induced
cross-dehydrogenative
coupling
of
C(sp3)-H
bonds
with
phenols
using
BrCCl3
to
give
aryl
alkyl
ethers
has
been
achieved
under
transition-metal-
and
photocatalyst-free
conditions.
This
operationally
simple
mild
protocol
a
broad
substrate
scope,
was
applied
the
modification
drug
molecules
on
gram-scale
synthesis.
phenolate
ion
functions
as
both
photosensitizer,
serves
oxidant
hydrogen
atom
transfer
(HAT)
agent.
Язык: Английский
Enhanced corrosion resistance of silicone resin: grafting nano-TiO2 onto graphene oxide via thiol–ene click chemistry
New Journal of Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
Using
a
thiol–ene
click
chemistry
method,
GO
and
TiO
2
are
grafted
to
the
silicone
resin
matrix
coating
for
creating
high
dispersion
interfacial
compatibility.
This
composite
displayed
an
anti-corrosion
feature
self-cleaning
property.
Язык: Английский
Chiral Bis(binaphthyl) Cyclopentadienyl Ligands for Rhodium-Catalyzed Desymmetrization of Diarylmethanes via Selective Arene Coordination
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
unknown
Опубликована: Сен. 18, 2024
Owing
to
substantial
advances
in
the
past
several
decades,
transition-metal-catalyzed
asymmetric
reactions
have
garnered
considerable
attention
as
pivotal
methods
for
constructing
chiral
molecules
from
abundant,
readily
available
achiral
counterparts.
These
are
largely
attributed
development
of
ligands
that
control
stereochemistry
through
steric
repulsion
and
other
noncovalent
interactions
between
functional
groups
or
prochiral
centers
on
substrates.
However,
stereocontrol
weakens
dramatically
with
increasing
distance
reaction
site
group
center.
Herein,
we
report
a
symphonic
strategy
remote
Rh(III)-catalyzed
benzylic
C-H
bond
addition
diarylmethanes
which
two
aryl
motifs
differ
at
Язык: Английский
Strategies for Arene Dissociation from Transition Metal eta-6-Arene Complexes
Dalton Transactions,
Год журнала:
2024,
Номер
unknown
Опубликована: Янв. 1, 2024
Transition
metal
η
6
-arene
complexes
have
unique
properties
that
facilitate
a
variety
of
arene
substitution
reactions,
rendering
π-activation
powerful
approach
for
functionalization.
Язык: Английский
Exploring the Site Selectivity of Arene Oxidation in [(η5-C5Me5)Ir(η6-arene)](OTf)2 Complexes
Organometallics,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 26, 2024
The
oxidation
selectivity
of
the
η6-arene
ligand
in
a
series
[(η5-C5Me5)Ir(η6-arene)](OTf)2
complexes
to
corresponding
[(η5-C5Me5)Ir(η5-phenoxo)](OTf)
derivatives
was
studied
as
complementary
protocol
metal-catalyzed
borylation-oxidation.
A
representative
compounds
prepared
with
mono-,
di-,
and
trisubstituted
arenes
well
two
examples
biphenyls
rationally
explore
site
C(sp2)–H
oxidation.
isolated
organometallic
arene
were
treated
NaClO2
formed
desired
iridium
η5-phenoxo
products.
While
site-selective
observed
for
some
compounds,
most
yielded
mixture
regioisomers.
Regioselectivity
primarily
determined
by
electronic
factors,
while
sterics
influenced
sites
that
electronically
similar.
Язык: Английский