A
visible-light-induced
method
for
the
hydrodichloromethylation
of
unactivated
alkenes
using
chloroform
(CHCl3)
was
developed,
employing
pyridine·BH3
as
halogen
atom
transfer
(XAT)
reagent.
The
strategy
showed
a
broad
functional
group
tolerance,
and
29
examples
alkenes,
including
complex
natural
products
or
drug
derivatives,
have
been
established
with
good
yields.
Mechanistic
studies
indicated
that
CHCl3
serves
both
source
dichloromethyl
radical
hydrogen
(HAT)
reagent,
borane
short-chain
reaction
process
involved
in
this
system.
This
represents
novel
approach
without
an
additional
HAT
ACS Catalysis,
Год журнала:
2025,
Номер
unknown, С. 1294 - 1304
Опубликована: Янв. 7, 2025
Given
the
widespread
presence
of
spirocyclic
scaffolds
in
natural
products
and
pharmacologically
relevant
synthetic
compounds,
development
efficient
methodologies
for
their
construction
holds
great
importance
medicinal
chemistry
pharmaceutical
research.
In
this
study,
a
general
photochemical
dearomative
spirocyclization
nonactivated
arenes
has
been
established.
The
key
to
method
lies
ability
amine-borane
radicals
activate
aryl
bromides
iodides
via
halogen-atom
transfer,
thereby
allowing
conversion
halides
into
corresponding
subsequent
chemodivergent
transformations.
remarkable
compatibility
versatility
1,4-difunctionalization
is
showed
by
rapid
assembly
structurally
diverse
1,4-cyclohexadiene-based
spirocycles
incorporating
oxindole,
indoline,
or
dihydrobenzofuran
subunits.
Moreover,
potential
utility
protocol
exemplified
formal
total
synthesis
vasopressin
V2
receptor
antagonist
Satavaptan.
Decyanation
after
α-functionalization
by
exploiting
the
inherent
properties
of
cyano
groups
enables
strategic
assembly
a
carbon
scaffold.
Herein,
we
demonstrate
an
amine-ligated
boryl
radical-mediated
group
transfer
(CGT)
strategy
malononitriles
under
photocatalytic
conditions.
This
allows
for
cleavage
C(sp3)–CN
and
formation
C(sp3)–D
C(sp3)
to
realize
decyanative
deuteration
cyclization
via
radical-polar
crossover.
Computational
studies
successfully
demonstrated
reactivity
CGT
promoters
can
be
accurately
assessed.
Chemical Science,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
Nitriles
stabilize
neutral
diarylboryl
radicals,
generating
the
RCN-BAr
2
complex,
an
efficient
boron-nitrogen
synthon
that
reacts
with
imines
and
olefins
for
photocatalytic
synthesis
of
boron–nitrogen
heterocycles,
such
as
1,4,2-diazaboroles.
Abstract
Allylic
amide
moieties
are
commonly
encountered
in
natural
products
and
privileged
structures
pharmaceuticals
agrochemicals.
Moreover,
because
allylic
can
be
to
converted
into
an
array
of
high‐value
motifs,
they
have
been
widely
employed
organic
synthesis.
However,
the
development
catalytic
systems
for
intermolecular
amidation
olefins,
particularly
branched
α
‐olefins,
has
proven
challenging.
Here,
a
biomimetic,
synergistic
method
is
reported
that
combines
photoredox,
cobalt,
Brønsted
base
catalysis
synthesis
substituted
amides
from
‐olefins
simple
imides
without
using
oxidants.
This
low‐cost,
operationally
features
broad
substrate
scope
excellent
functional
group
compatibility.
it
successfully
used
functionalization
several
structurally
complex
molecules
demonstrating
method's
potential
utility
medicinal
chemistry
applications.
Mechanistic
studies
revealed
C(
sp
3
)─N
bond
formation
mediated
by
nitrogen‐centered
radical
intermediate,
which
generated
via
sequence
involving
deprotonation
single‐electron
oxidation.
Organic Letters,
Год журнала:
2024,
Номер
26(43), С. 9263 - 9268
Опубликована: Окт. 21, 2024
Here,
we
present
a
metal-free
photosensitized
three-component
reaction
for
the
carboimination
of
alkenes
based
on
oxime
carbonates.
Homolysis
carbonates
via
light-mediated
energy
transfer
enables
simultaneous
generation
iminyl
radicals
and
alkoxycarbonyloxyl
radicals.
The
alkoxy
can
act
as
an
effective
hydrogen
atom
reagent,
abstracting
atoms
from
alkanes
aldehydes,
silanes,
phosphine
oxide.
This
strategy
exhibits
broad
functional
group
tolerance
under
mild
conditions,
further
broadening
diversity
alkene
carboimination.
Organic Letters,
Год журнала:
2024,
Номер
26(43), С. 9282 - 9287
Опубликована: Окт. 23, 2024
In
this
study,
we
investigated
the
photocatalytic
decarboxylation
of
trimethylamine
carboxyborane
under
mild
conditions,
successfully
generating
boryl
radicals
for
subsequent
borylation
reactions
with
imines
and
various
alkenes.
This
method
exhibited
broad
substrate
compatibility,
including
functionalization
biologically
relevant
molecules.
Our
findings
expand
utility
beyond
its
role
as
a
carbon-monoxide-
drug-releasing
agent,
highlighting
potential
in
radical
chemistry
through
decarboxylation.
work
establishes
robust
foundation
further
exploration
synthetic
application
carboxyborane.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(14), С. 10223 - 10233
Опубликована: Июнь 28, 2024
A
photo-induced
cascade
sulfone
alkylation/cyclization
of
2-isocyanoaryl
thioethers
is
explored.
This
visible-light-triggered
reaction
not
only
occurs
under
extremely
mild
conditions
but
also
does
require
the
presence
a
photosensitizer.
The
photocatalytic
process
triggered
by
photochemical
activity
in
situ-generated
electron
donor–acceptor
complexes,
arising
from
association
and
α-iodosulfones.
radical
pathway
was
confirmed
UV–vis
spectroscopy,
trapping,
Job's
plot,
on/off
irradiation
experiments.
ACS Catalysis,
Год журнала:
2024,
Номер
unknown, С. 17547 - 17555
Опубликована: Ноя. 13, 2024
In
the
modern
era
of
organic
synthesis,
mechanisms
centered
on
radical
intermediates
have
become
increasingly
impactful.
Among
all
these,
hydrogen
atom
transfer
(HAT)
represents
one
most
fundamental
chemical
reaction
steps
and
has
found
applications
in
designing
practical
transformations.
Herein,
we
present
a
detailed
case
study
selective
hydrodefluorination
trifluoromethylarenes
utilizing
N-heterocyclic
carbene
boranes
(NHC-boranes)
as
donor.
Under
optimal
conditions
featuring
an
acridine-based
photocatalyst,
complete
selectivity
for
mono-hydrodefluorination
was
achieved
across
wide
array
substrates.
Comprehensive
mechanistic
studies
combining
experimental
computational
approaches
disproved
chain
process
involving
fluorine
but
rather
pointed
to
HAT
non-chain
mechanism,
where
key
step
involves
difluorobenzylic
abstracting
from
NHC-borane
generate
boryl
polarity-matched
fashion.
Evaluation
selection
Lewis
base-ligated
revealed
molecular
descriptors
critical
outcomes
this
reaction,
classification
model
built
explain
structure–reactivity
relationship
how
various
elementary
can
be
influenced.
These
results
collectively
provide
valuable
information
future
design
increase
utility
chemistry.
Organic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(17), С. 4785 - 4793
Опубликована: Янв. 1, 2024
Reported
herein
is
a
method
that
merges
organophotoredox
and
hydrogen
atom
transfer
catalysis
to
enable
the
C–H
borylation
of
heterocycles
using
O
2
as
an
environmentally
friendly
oxidant.
