Angewandte Chemie,
Год журнала:
2024,
Номер
136(23)
Опубликована: Апрель 3, 2024
Abstract
Catalytic
methods
allowing
for
the
reliable
prediction
and
control
of
diverse
regioselectivity
along
with
enantioselectivity
to
access
different
regio‐
enantiomers
by
switching
least
reaction
parameters
are
one
most
attractive
ways
in
organic
synthesis,
which
provide
enantioenriched
architectures
from
identical
starting
materials.
Herein,
a
Co‐catalyzed
regiodivergent
enantioselective
reductive
hydroalkylation
1,3‐dienes
aldehydes
has
been
achieved,
furnishing
homoallylic
alcohol
good
levels
enantioselectivity.
The
features
switch
tuned
selection
proton
source.
use
an
acid
as
source
provided
asymmetric
1,2‐hydroalkylation
products
under
conditions,
yet
4,3‐hydroalkylation
were
obtained
silane
hydride
This
catalytic
protocol
allows
alcohols
two
continuous
saturated
carbon
centers
regio‐,
diastereo‐,
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(7), С. 4380 - 4392
Опубликована: Фев. 1, 2024
The
hydrofluorination
of
alkenes
represents
an
attractive
strategy
for
the
synthesis
aliphatic
fluorides.
This
approach
provides
a
direct
means
to
form
C(sp3)–F
bonds
selectively
from
readily
available
alkenes.
Nonetheless,
conducting
using
nucleophilic
fluorine
sources
poses
significant
challenges
due
low
acidity
and
high
toxicity
associated
with
HF
poor
nucleophilicity
fluoride.
In
this
study,
we
present
new
Co(salen)-catalyzed
simple
utilizing
Et3N·3HF
as
sole
source
both
hydrogen
fluorine.
process
operates
via
photoredox-mediated
polar-radical-polar
crossover
mechanism.
We
also
demonstrated
versatility
method
by
effectively
converting
diverse
array
activated
varying
degrees
substitution
into
hydrofluorinated
products.
Furthermore,
successfully
applied
methodology
18F-hydrofluorination
reactions,
enabling
introduction
18F
potential
radiopharmaceuticals.
Our
mechanistic
investigations,
conducted
rotating
disk
electrode
voltammetry
DFT
calculations,
unveiled
involvement
carbocation
CoIV–alkyl
species
viable
intermediates
during
fluorination
step,
contribution
each
pathway
depends
on
structure
starting
alkene.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(19)
Опубликована: Фев. 28, 2024
Abstract
We
report
a
general,
intramolecular
cycloisomerization
of
unactivated
olefins
with
pendant
nucleophiles.
The
reaction
proceeds
under
mild
conditions
and
tolerates
ethers,
esters,
protected
amines,
acetals,
pyrazoles,
carbamates,
arenes.
It
is
amenable
to
N
‐,
O
as
well
C
‐nucleophiles,
yielding
number
different
heterocycles
including,
but
not
limited
to,
pyrrolidines,
piperidines,
oxazolidinones,
lactones.
Use
both
benzothiazinoquinoxaline
organophotocatalyst
Co‐salen
catalyst
obviates
the
need
for
stoichiometric
oxidant
or
reductant.
showcase
utility
protocol
in
late‐stage
drug
diversification
synthesis
several
small
natural
products.
JACS Au,
Год журнала:
2025,
Номер
5(2), С. 426 - 447
Опубликована: Янв. 29, 2025
Many
important
synthetic-oriented
works
have
proposed
excited
organic
radicals
as
photoactive
species,
yet
mechanistic
studies
raised
doubts
about
whether
they
can
truly
function
photocatalysts.
This
skepticism
originates
from
the
formation
of
(photo)redox-active
degradation
products
and
picosecond
decay
electronically
radicals,
which
is
considered
too
short
for
diffusion-based
photoinduced
electron
transfer
reactions.
From
this
perspective,
we
analyze
synthetic
transformations
where
been
photocatalysts,
comparing
their
theoretical
maximum
state
potentials
with
required
observed
photocatalytic
reactivity.
We
summarize
structurally
similar
photocatalysts
indicating
different
reaction
pathways
some
catalytic
systems,
addressing
cases
radical
exceed
Additionally,
perform
a
kinetic
analysis
to
explain
in
on
subpicosecond
time
scales.
further
rationalize
potential
anti-Kasha
reactivity
higher
states
femtosecond
lifetimes,
highlighting
how
future
photocatalysis
advancements
could
unlock
new
photochemical
pathways.
Angewandte Chemie International Edition,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 21, 2025
Recently,
in
a
communication
to
this
journal,
Qiao,
Jang,
and
coworkers
described
an
asymmetric
photoredox
reaction
promoted
by
TADF
cyanoarene
photocatalysts
(specifically
4DPAPN
(3,4,5,6-tetrakis(diphenylamino)phthalonitrile)).
The
authors
claimed
that
the
high
reduction
potential
required
for
acetonitrile
was
achieved
radical
anion
of
photocatalyst
its
excited
state,
which
initiated
reaction.
This
mechanism
is
usually
named
consecutive
photoinduced
electron
transfer
(ConPeT),
two
photons
are
involved:
first
one
excite
generate
4DPAPN•-
second
photon
promote
state
*4DPAPN•-.
Employing
ultrafast
transient
absorption
spectroscopy,
here
we
report
that,
although
indeed
involved
transformation,
*4DPAPN•-
short-lived,
not
emissive,
quenched
organic
substrate
employed
reaction,
opposite
what
authors.
can
solvated
able
reduce
chemistry.
It
worth
noting
different
photochemical
likely
be
operative
CH2Cl2,
where
electrons
much
less
stabilized
solvent
might
occur.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(23)
Опубликована: Апрель 3, 2024
Abstract
Catalytic
methods
allowing
for
the
reliable
prediction
and
control
of
diverse
regioselectivity
along
with
enantioselectivity
to
access
different
regio‐
enantiomers
by
switching
least
reaction
parameters
are
one
most
attractive
ways
in
organic
synthesis,
which
provide
enantioenriched
architectures
from
identical
starting
materials.
Herein,
a
Co‐catalyzed
regiodivergent
enantioselective
reductive
hydroalkylation
1,3‐dienes
aldehydes
has
been
achieved,
furnishing
homoallylic
alcohol
good
levels
enantioselectivity.
The
features
switch
tuned
selection
proton
source.
use
an
acid
as
source
provided
asymmetric
1,2‐hydroalkylation
products
under
conditions,
yet
4,3‐hydroalkylation
were
obtained
silane
hydride
This
catalytic
protocol
allows
alcohols
two
continuous
saturated
carbon
centers
regio‐,
diastereo‐,
Chemical Science,
Год журнала:
2024,
Номер
15(36), С. 14739 - 14745
Опубликована: Янв. 1, 2024
The
strong
photoreducing
abilities
of
the
investigated
TADF
chromophores
is
result
photogeneration
solvated
electrons
in
a
consecutive
two-photon
induced
mechanism
(ConPies).
Advanced Synthesis & Catalysis,
Год журнала:
2024,
Номер
366(6), С. 1306 - 1314
Опубликована: Янв. 26, 2024
Abstract
Herein,
we
report
a
modular
photocatalytic
platform
for
the
site‐selective
pyridination
of
saturated
hydrocarbon
compounds
employing
organic
photoredox
catalysis
to
forge
new
carbon‐carbon
bonds.
The
C−H
could
couple
benzylic/allylic
bonds
with
pyridylphosphonium
salts,
which
installed
directly
and
regioselectively
from
heteroarenes
through
radical‐radical
cross
coupling
mechanism.
This
synthetic
methodology
tolerate
variety
functional
groups,
complex
heteroarenes,
even
late‐stage
functionalization
pharmaceuticals
selectively.
Chemical Science,
Год журнала:
2024,
Номер
15(11), С. 4114 - 4120
Опубликована: Янв. 1, 2024
Starting
from
the
same
substrates,
tunable
C–H
functionalization
and
dearomatization
have
been
achieved
under
catalysis
of
a
new
organic
photocatalyst
–
isoazatruxene
ITN-2.
European Journal of Organic Chemistry,
Год журнала:
2024,
Номер
27(28)
Опубликована: Май 20, 2024
Abstract
In
recent
years,
the
functionalization
of
1,3‐butadiene
has
become
an
attractive
strategy
for
constructing
allyl
compounds
with
molecular
and
structural
complexity,
current
research
focuses
on
synthetic
chemistry
organic
synthesis.
Compared
traditional
synthesis
method,
methods
promoted
by
photochemistry
or
electrochemistry
represent
environmentally
friendly
mild
strategy.
this
review,
reactions
under
photochemical/electrochemical
processes
in
years
are
reviewed
according
to
classification
systems,
particular
emphasis
corresponding
reaction
mechanism,
which
lays
a
foundation
further
exploration
new
catalytic
methods.
