Organic Letters,
Год журнала:
2020,
Номер
22(21), С. 8500 - 8504
Опубликована: Окт. 12, 2020
An
efficient
radical
transannulation
reaction
of
pyridotriazoles
with
isothiocyanates
and
xanthate
esters
was
developed.
This
method
features
conversion
into
two
N-fused
heterocyclic
aromatic
systems—imino-thiazolopyridines
oxo-thiazolopyridine
derivatives—via
one-step
Co(II)-catalyzed
proceeding
via
a
mechanism.
The
synthetic
usefulness
the
developed
illustrated
in
synthesis
amino
acid
derivatives
further
transformations
obtained
products.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
61(4)
Опубликована: Окт. 30, 2021
The
photolysis
of
diazoalkanes
to
conduct
singlet
carbene
transfer
reactions
colored
has
recently
attracted
significant
interest
in
organic
synthesis.
Herein,
we
describe
a
photocatalytic
approach
that
allows
the
access
triplet
intermediates
via
energy
highly
efficient
gem-difluoroolefination
with
α-trifluoromethyl
styrenes.
use
tertiary
amines
proved
pivotal
unlock
this
unusual
reaction
pathway
and
prevent
undesired
cyclopropanation
pathways.
amine
further
facilitates
ultimate
abstraction
fluoride
yield
gem-difluoroolefins
(43
examples,
up
88
%
yield),
which
is
supported
by
experimental
theoretical
mechanistic
studies.
We
explored
synthesis
method
broad
substrate
scope,
ranging
from
simple
olefins
heterocyclic
towards
decoration
pharmaceutically
relevant
building
blocks.
Journal of the American Chemical Society,
Год журнала:
2021,
Номер
143(29), С. 11121 - 11129
Опубликована: Июль 20, 2021
A
highly
efficient
catalytic
method
has
been
developed
for
asymmetric
radical
cyclopropanation
of
alkenes
with
in
situ-generated
α-heteroaryldiazomethanes
via
Co(II)-based
metalloradical
catalysis
(MRC).
Through
fine-tuning
the
cavity-like
environments
newly-synthesized
Chemical Science,
Год журнала:
2022,
Номер
13(11), С. 3273 - 3280
Опубликована: Янв. 1, 2022
Visible
light
induced
singlet
nucleophilic
carbenes
undergo
rapid
[2
+
1]-cycloaddition
with
tethered
olefins
to
afford
unique
bicyclo[3.1.0]hexane
and
bicyclo[4.1.0]heptane
scaffolds.
This
cyclopropanation
process
requires
only
visible
irradiation
proceed,
circumventing
the
use
of
exogenous
(photo)catalysts,
sensitisers
or
additives
showcases
a
vastly
underexplored
mode
reactivity
for
in
chemical
synthesis.
The
discovery
additional
transformations
including
cyclopropanation/retro-Michael/Michael
cascade
chromanones
photochemical
C-H
insertion
reaction
are
also
described.
ACS Catalysis,
Год журнала:
2022,
Номер
12(9), С. 5510 - 5516
Опубликована: Апрель 25, 2022
We
developed
an
efficient
visible-light-mediated
formal
carbene
insertion
reaction
of
1,3-diketones
with
diazoesters
for
the
construction
enantioenriched
1,4-dicarbonyl
compounds
a
quaternary
carbon
center.
Combining
visible
light
and
Brønsted
acid
catalyst,
chiral
were
achieved
in
good
yields
high
enantioselectivities
by
photochemical
transfer
protocol.
European Journal of Organic Chemistry,
Год журнала:
2022,
Номер
2022(44)
Опубликована: Окт. 21, 2022
Abstract
Cyclopropanes
are
one
of
the
most
important
strained
rings
existing
in
various
pharmaceutical
products
and
secondary
metabolites.
They
also
widely
used
total
synthesis
natural
products,
medicinal
chemistry,
materials
science.
In
past
years,
photochemical
cyclopropanation
has
been
gradually
developed
as
a
robust
attractive
synthetic
method
to
prepare
diverse
cyclopropane
backbones.
this
review,
we
summarize
recent
advances
visible
light‐mediated
synthesis,
especially
using
carbene
transfer
strategy
photocatalytic
radical
reactions.
Chemical Science,
Год журнала:
2022,
Номер
14(4), С. 843 - 848
Опубликована: Ноя. 29, 2022
While
asymmetric
insertion
of
metal
carbenes
into
H-X
(X
=
C,
N,
O,
etc.)
bonds
has
been
well-established,
control
over
free
is
challenging
due
to
the
presence
strong
background
reactions
and
lack
any
anchor
for
a
catalyst
interaction.
Here
we
have
achieved
first
photo-induced
metal-free
bond
this
type.
With
visible
light
used
as
promoter
chiral
phosphoric
acid
catalyst,
α-diazoesters
aryl
amines
underwent
smooth
N-H
form
enantioenriched
α-aminoesters
with
high
efficiency
good
enantioselectivity
under
mild
conditions.
Key
success
was
use
DMSO
an
additive,
which
served
rapidly
capture
highly
reactive
carbene
intermediate
domesticated
sulfoxonium
ylide.
ACS Catalysis,
Год журнала:
2023,
Номер
13(14), С. 9806 - 9816
Опубликована: Июль 11, 2023
Cyclopropanes
bearing
contiguous
all-carbon
quaternary
centers
continue
to
attract
attention
due
their
bioactivities.
However,
methods
obtain
cyclopropanes
with
remain
largely
unexplored
the
high
steric
hindrance
of
these
compounds.
Herein,
we
report
a
visible-light-mediated
energy-transfer
(EnT)
strategy
realize
in
situ
donor/donor
carbenes
from
readily
available
N-tosylhydrazones,
facilitating
synthesis
highly
congested
EWG-free
cyclopropanes.
Through
this
approach,
are
rapidly
installed
into
complex
bioactive
molecules,
fluorescent
and
other
useful
building
blocks
that
challenging
synthesize.
Detailed
mechanistic
reactions
DFT
studies
clearly
demonstrated
role
photosensitizer,
formation
carbenes,
necessity
light
base
system.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(15)
Опубликована: Фев. 14, 2023
Free
carbene
readily
causes
multiple
side
reactions
due
to
its
high
energy,
thus
asymmetric
transformation
is
very
difficult.
We
present
here
our
findings
of
high-pKa
Brønsted
acid
catalysts
that
enable
free
insertion
into
N-H
bonds
amines
prepare
chiral
α-amino
derivatives
with
enantioselectivity.
Under
irradiation
visible
light,
diazo
compounds
produce
high-energy
carbenes
are
captured
by
form
ylide
intermediates,
and
then
the
newly
designed
acids,
spiro
phosphamides,
promote
proton
transfer
ylides
afford
products.
Computational
kinetic
studies
uncover
principle
for
rational
design
proton-transfer
explain
how
accelerate
this
provide
stereocontrol.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 29, 2025
Imine-containing
azaarene-based
triarylmethanes
are
vital
molecular
motifs
that
prevalent
in
a
wide
array
of
bioactive
compounds.
Recognizing
the
limitations
current
synthetic
methodologies─marked
by
scarcity
examples
and
difficulties
flexible
functional
group
modulation─we
have
developed
an
efficient
modular
asymmetric
photochemical
strategy
employing
pyridotriazoles
boronic
acids
as
substrates.
Utilizing
novel
chiral
diamine-derived
pyrroles
primary
amines
catalysts,
we
successfully
synthesized
diverse
range
with
high
yields
excellent
enantioselectivities.
This
method
not
only
exhibits
broad
substrate
scope
outstanding
tolerance
but
also
enables
precise
synthesis
deuterated
derivatives
using
inexpensive
D2O
deuterium
source.
Mechanistic
studies
reveal
unusual
1,4-boron
shift
is
critical
step
generating
boronated
enamine
intermediate,
while
shedding
light
on
potential
enantiocontrol
mechanisms
facilitated
catalyst.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
61(1)
Опубликована: Окт. 27, 2021
A
mild
visible
light-induced
palladium-catalyzed
alkyl
Heck
reaction
of
diazo
compounds
and
N-tosylhydrazones
is
reported.
broad
range
vinyl
arenes
heteroarenes
with
high
functional
group
tolerance,
as
well
a
different
compounds,
can
efficiently
undergo
this
transformation.
This
method
features
Brønsted
acid-assisted
generation
hybrid
palladium
C(sp3
)-centered
radical
intermediate,
which
allowed
for
new
selective
C-H
functionalization
protocol.
