Organic Letters,
Год журнала:
2022,
Номер
24(17), С. 3265 - 3269
Опубликована: Апрель 25, 2022
The
bulk
industrial
chemical
2-bromo-3,3,3-trifluoropropene
(BTP)
was
first
employed
as
a
coupling
partner
in
photocatalytic
defluorinative
reactions
with
N-aryl
amino
acids.
Photoredox
activation
of
the
C(sp2)–Br
bond
resultant
2-bromo-1,1-difluoroalkenes
generates
gem-difluoro
vinyl
radicals
for
further
radical
cyclization.
Various
4-(difluoromethylidene)-tetrahydroquinolines
were
assembled
good
yields
by
combining
two
photoredox
cycles
single
photocatalyst.
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(19), С. 13610 - 13621
Опубликована: Сен. 11, 2023
An
electrophilic
spirocyclization
of
N-benzylacrylamides
with
N-halosuccinimides
(NXS)
as
the
halogenating
reagents
has
been
developed.
This
reaction
is
carried
out
at
room
temperature
under
simple
conditions
without
relying
on
metal
reagents,
photochemistry,
or
electrochemistry,
providing
a
fast
and
efficient
route
to
synthesize
wide
variety
4-halomethyl-2-azaspiro[4.5]decanes
satisfactory
yields.
The
approach
further
highlighted
through
gram-scale
synthesis
diverse
transformations
spiro
products.
Journal of the American Chemical Society,
Год журнала:
2020,
Номер
142(28), С. 12420 - 12429
Опубликована: Июль 2, 2020
By
utilizing
an
underexplored
reactivity
mode
of
N-aminopyridinium
ylides,
we
developed
the
visible-light-induced
ortho-selective
aminopyridylation
alkenes
via
radical-mediated
1,3-dipolar
cycloaddition.
The
photocatalyzed
single-electron
oxidation
ylides
generates
corresponding
radical
cations
that
enable
previously
inaccessible
1,3-cycloaddition
with
a
broader
range
alkene
substrates.
resulting
cycloaddition
adducts
rapidly
undergo
subsequent
homolytic
cleavage
N-N
bond,
conferring
substantial
thermodynamic
driving
force
to
yield
various
β-aminoethylpyridines.
Remarkably,
amino
and
pyridyl
groups
can
be
installed
into
both
activated
unactivated
modular
control
ortho-selectivity
1,2-syn-diastereoselectivity
under
metal-free
mild
conditions.
Combined
experimental
computational
studies
are
conducted
clarify
detailed
reaction
mechanism
origins
site
selectivity
diastereoselectivity.
Nature Communications,
Год журнала:
2021,
Номер
12(1)
Опубликована: Май 17, 2021
Abstract
Development
of
practical
deuteration
reactions
is
highly
valuable
for
organic
synthesis,
analytic
chemistry
and
pharmaceutic
chemistry.
Deuterodehalogenation
chlorides
tends
to
be
an
attractive
strategy
but
remains
a
challenging
task.
We
here
develop
photocatalytic
system
consisting
aryl-amine
photocatalyst
disulfide
co-catalyst
in
the
presence
sodium
formate
as
electron
hydrogen
donor.
Accordingly,
many
aryl
chlorides,
alkyl
other
halides
are
converted
deuterated
products
at
room
temperature
air
(>90
examples,
up
99%
D-incorporation).
The
mechanistic
studies
reveal
that
amine
serves
reducing
photoredox
catalyst
initiate
cleavage
C-Cl
bond,
same
time
energy
transfer
induce
homolysis
consequent
deuterium
process.
This
economic
environmentally-friendly
method
can
used
site-selective
D-labeling
number
bioactive
molecules
direct
H/D
exchange
some
drug
molecules.
Journal of the American Chemical Society,
Год журнала:
2020,
Номер
142(23), С. 10485 - 10493
Опубликована: Апрель 30, 2020
Geminal
diboronates
have
attracted
significant
attention
because
of
their
unique
structures
and
reactivity.
However,
benzofuran-,
indole-,
benzothiophene-based
benzylic
gem-diboronates,
building
blocks
for
biologically
relevant
compounds,
are
unknown.
A
promising
protocol
using
visible
light
aryl
iodides
constructing
valuable
blocks,
including
via
radical
carbo-cyclization/gem-diborylation
alkynes
with
a
high
functional
group
tolerance
is
presented.
The
utility
these
gem-diboronates
has
been
demonstrated
by
10
g
scale
conversion,
versatile
transformations,
the
synthesis
approved
drug
scaffolds
two
drugs,
even
polymer
synthesis.
mechanistic
investigation
indicates
that
merging
dinuclear
gold
catalyst
(photoexcitation
315–400
nm
UVA
light)
Na2CO3
directly
responsible
photosensitization
254
UV
blue
LED
(410–490
nm,
λmax
=
465
nm)
through
an
energy
transfer
(EnT)
process,
followed
homolytic
cleavage
C–I
bond
in
iodide
substrates.
Two-dimensional
metal-organic
nanosheets
(2D
MONs)
are
an
emerging
class
of
ultrathin,
porous,
and
crystalline
materials.
The
organic/inorganic
hybrid
nature
offers
MONs
distinct
advantages
over
other
inorganic
in
terms
diversity
organic
ligands
metal
notes.
Compared
to
bulk
three-dimensional
frameworks,
2D
possess
merits
high
density
readily
accessible
catalytic
sites,
reduced
diffusion
pathways
for
reactants/products,
fast
electron
transport.
These
features
endow
with
enhanced
physical/chemical
properties
ideal
heterogeneous
catalysis.
In
this
Review,
state-of-the-art
synthetic
methods
the
fabrication
were
summarized.
advances
MONs-based
materials
electrocatalysis
photocatalysis,
including
hydrogen
evolution
reaction
(HER),
oxygen
(OER),
reduction
(ORR),
carbon
dioxide
(CO2
RR),
electro-/photocatalytic
transformations
systematically
discussed.
Finally,
challenges
perspectives
regarding
future
design
synthesis
high-performance
photocatalysis
provided.
Organic Letters,
Год журнала:
2023,
Номер
25(12), С. 2129 - 2133
Опубликована: Март 21, 2023
Herein,
we
disclose
a
facile
and
versatile
trifluoromethylimination
of
alkene
with
rationally
designed
N-(diphenylmethylene)-1,1,1-trifluoromethanesulfonamide
as
bench-stable
readily
accessible
carboamination
reagent.
Enabled
by
an
energy
transfer
(EnT)
process,
array
alkenes
were
able
to
be
facilely
CF3-iminated
under
metal-free
photocatalytic
conditions.
The
mild
reaction
conditions
good
functional
group
compatibility
render
this
protocol
highly
valuable
for
the
difunctionalization
olefins
structural
complexity
diversity.
ACS Catalysis,
Год журнала:
2024,
Номер
14(12), С. 9283 - 9293
Опубликована: Июнь 4, 2024
The
direct
reductive
functionalization
of
alkynes
under
mild
conditions
presents
a
promising
yet
challenging
avenue
for
accessing
value-added
molecules.
Alkyne
radical
anions
represent
distinct
class
reactive
intermediates
characterized
by
both
charge
and
an
unpaired
electron,
thus
holding
great
potential
facilitating
diverse
bond
formations,
particularly
in
alkyne
functionalization.
However,
the
synthetic
utility
is
limited,
primarily
due
to
difficulty
their
generation
formation
highly
unstable
vinyl
intermediates.
In
this
study,
we
accomplished
from
aryl
feedstocks
via
single
electron
transfer
(SET)
reduction
with
photogenerated
CO2
anion
(CO2•–),
enabling
hydroalkylation,
arylalkenylation,
hydrocarboxylation
alkynes.
Our
photocatalytic
strategy
features
metal-free
catalysis,
reaction
conditions,
employment
traceless
reductant,
good
functional
group
compatibility,
step-
atom-economy,
high
regioselectivity.
This
study
not
only
paves
way
leveraging
underexplored
but
also
catalyzes
ongoing
exploration
bifunctional
CO2•–
species
chemistry.
Angewandte Chemie International Edition,
Год журнала:
2020,
Номер
59(50), С. 22514 - 22522
Опубликована: Авг. 31, 2020
Abstract
Bioconjugation
methods
using
visible‐light
photocatalysis
have
emerged
as
powerful
synthetic
tools
for
the
selective
modification
of
biomolecules
under
mild
reaction
conditions.
However,
number
photochemical
transformations
that
allow
successful
protein
bioconjugation
is
still
limited
because
need
stringent
Herein,
we
report
a
newly
developed
water‐compatible
fluorescent
photosensitizer
Q
PEG
can
be
used
visible‐light‐induced
cysteine‐specific
installation
by
exploiting
its
intrinsic
photosensitizing
ability
to
activate
S−H
bond
cysteine.
The
slightly
modified
CAT
enables
effective
photocatalytic
conjugation
biologically
relevant
groups.
superior
reactivity
and
cysteine
selectivity
this
methodology
was
further
corroborated
traceless
with
series
complex
peptides
proteins
biocompatible
A
strategy
integrating
near
infrared
(NIR)
photothermal
and
catalytic
effects
within
one
active
center
beyond
ultraviolet
visible
light
is
proposed
without
the
combination
of
separated
transformation
components.
giant
polyoxomolybdate,
which
has
high
NIR
conversion
efficiency,
selected
as
model
catalyst,
while
a
cationic
β-cyclodextrin
used
to
cover
its
negatively
charged
surface
electrostatically.
Under
radiation,
designed
catalyst
increases
activity
cyclohexene
oxidation
under
O2
atmosphere
in
water.
The
reaches
about
pentaploid
reaction
radiation.
By
excluding
heating
effect
from
external
heater
at
same
temperature,
twice
much
enhancement,
can
be
attributed
sole
action,
still
observed.
While
shielded
by
organic
porous
layer,
cavity
allows
integrated
conduct
selective
catalysis
screening
molecules
size
over
channel.