We
demonstrate
1)
that
halogen
bonding
is
not
critical
for
enabling
light-driven
radical
generation
from
diaryliodonium
salts
and
2)
radi-cals
generated
by
this
route
can
be
captured
transition-metals
C–H
arylation
reactions.
These
results
are
the
first
step
toward
devel-oping
new
metal-catalyzed
aryl
couplings
without
exogenous
photocatalysts.
Beilstein Journal of Organic Chemistry,
Год журнала:
2024,
Номер
20, С. 2891 - 2920
Опубликована: Ноя. 13, 2024
Diaryliodonium
salts
have
become
widely
recognized
as
arylating
agents
in
the
last
two
decades.
Both,
symmetrical
and
unsymmetrical
forms
of
these
serve
effective
electrophilic
reagents
various
organic
syntheses.
The
use
diaryliodoniums
C–C
carbon–heteroatom
bond
formations,
particularly
under
metal-free
conditions,
has
further
enhanced
popularity
reagents.
In
this
review,
we
concentrate
on
arylation
reactions
involving
carbon
other
heteroatoms,
encompassing
rearrangement
absence
any
metal
catalyst,
summarize
advancements
made
five
years.
ACS Catalysis,
Год журнала:
2024,
Номер
14(24), С. 18896 - 18906
Опубликована: Дек. 12, 2024
There
is
a
scarcity
of
general
strategies
for
the
site-selective
α–Csp3–H
arylation
glycine
derivatives
to
synthesize
nonproteinogenic
α-arylglycines
that
occur
frequently
in
commercial
drugs
and
bioactive
molecules.
We
disclose
copper-photoredox-catalyzed
using
diaryliodonium
reagents
(DAIRs)
as
arylating
agents.
This
strategy
harnesses
underexplored
ability
DAIRs
serve
agents
under
visible-light
irradiation
copper
salts
photocatalysts.
The
method
applies
glycine-selective
C–H
peptides
with
electronically
structurally
diverse
DAIRs.
Moreover,
we
demonstrate
photoinduced
copper-catalyzed
single
electron
transfer
(SET)
can
be
coupled
halogen
atom
(XAT)
process
presence
alkyl
iodides
accomplish
alkylation
glycines
peptides.
In
this
synergistic
SET/XAT
approach,
phenyl
radicals
generated
from
diphenyl
iodonium
triflate
mediate
XAT
generate
iodides.
Both
these
methods
operate
mild
conditions
exhibit
broad
scope
appreciable
functional
group
tolerance.
Overall,
divergent
toolbox
presented
here
facilitate
access
various
alkylated
arylated
enable
bioconjugation
between
drug
An
organo-photocatalyzed
approach
for
the
chemoselective
dealkylation
and
de-esterification
of
phenols
is
developed
by
employing
trimethyl
silyl
chloride
as
C‒O
bond
activator
9-Mes-10-MeAcr+ClO4‒
photoredox
catalyst.
This
method
demonstrates
an
exceptional
selectivity
towards
cleavage
phenolic
ethers
esters
over
equivalent
aliphatic
scaffolds,
presenting
a
broad
range
functional
group
sustainability.
strategy
also
enables
selective
debenzylation
in
presence
reduction-sensitive
groups.
The
photocatalytic
efficiency
was
further
extrapolated
fragmentation
lignin
models
synthetic
modification
manufacturing
FLAP
inhibitor.
Mechanistic
studies,
photophysical
experiments
computations
provide
evidence
involvement
oxonium
intermediate,
generated
through
photo-oxidation
arene
ring,
which
ultimately
leads
to
disintegration
bond,
facilitated
oxophilicity
silicon.
We
demonstrate
1)
that
halogen
bonding
is
not
critical
for
enabling
light-driven
radical
generation
from
diaryliodonium
salts
and
2)
radi-cals
generated
by
this
route
can
be
captured
transition-metals
C–H
arylation
reactions.
These
results
are
the
first
step
toward
devel-oping
new
metal-catalyzed
aryl
couplings
without
exogenous
photocatalysts.