Chemistry - An Asian Journal,
Год журнала:
2022,
Номер
17(19)
Опубликована: Авг. 8, 2022
Herein,
we
developed
two
distinct
pyridine
N-oxide
directed
C-H
activation
protocols
to
achieve
[4+1]
annulation
and
alkoxylation
of
benzamide
derivatives
by
merging
Co-catalysis
with
visible-light
photoredox
catalysis.
The
deliver
the
respective
products
in
good
yields
under
facile
conditions
at
room
temperature.
use
an
inexpensive
photocatalyst
coupled
molecular
oxygen
bypassing
need
stoichiometric
oxidants
forms
chief
highlight
work.
are
scalable
could
be
further
modified.
Additionally,
preliminary
studies
were
carried
out
probe
reaction
mechanism.
Organic Letters,
Год журнала:
2023,
Номер
25(10), С. 1722 - 1726
Опубликована: Март 4, 2023
Direct
N-allylation
of
azoles
with
hydrogen
evolution
has
been
achieved
through
the
synergistic
combination
organic
photocatalysis
and
cobalt
catalysis.
The
protocol
bypasses
stoichiometric
oxidants
prefunctionalization
alkenes
produces
(H2)
as
byproduct.
This
transformation
highlights
high
step-
atom-economy,
efficiency,
broad
functional
group
tolerance
for
further
derivatization,
which
opens
a
door
C-N
bond
formation
that
is
valuable
in
heterocyclic
chemistry.
ACS Catalysis,
Год журнала:
2023,
Номер
13(24), С. 16136 - 16147
Опубликована: Дек. 1, 2023
Herein,
we
report
the
rational
design
of
a
modular
dual
photoredox
and
cobalt
catalysis
paradigm
for
difunctionalization
unsaturated
hydrocarbons,
unlocking
synthesis
valuable
but
challenging
1,2-halonitroalkane
substrate
class.
The
protocol
relies
on
use
redox-active
organic
nitrating
reagent
N-nitrosuccinimide
as
source
nitryl
radicals
cobalt-mediated
radical
ligand
transfer
(RLT)
methodology
to
form
carbon–halogen
bond.
This
synergistic
cooperation
between
photocatalyst
high-valence
metal
center
occurs
under
mild
reaction
conditions
is
capable
delivering
1,2-chloronitro-
1,2-bromonitroalkanes
in
single
chemical
operation
while
exhibiting
high
functional-group
tolerance
exclusive
regioselectivity
variety
olefins.
Mechanistic
studies
based
both
experimental
spectroscopic
analysis
provided
insights
into
nature
this
catalytic
halo-nitration
process
including
evidence
halogen
catalyst.
Furthermore,
employing
net-neutral
radical/polar
crossover
(RPC)
approach
cobalt-free
allowed
us
accommodate
external
protic
nucleophiles,
thiols,
alcohols,
acids,
and,
notably,
substituted
amines.
Highly
functionalized
olefin
scaffolds
also
successfully
underwent
nitrative
difunctionalization,
demonstrating
viability
these
protocols
late-stage
functionalization
bioactive
molecules.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(35)
Опубликована: Июнь 7, 2024
We
report
a
photochemical
method
for
the
semipinacol
rearrangement
of
unactivated
allylic
alcohols.
Aliphatic
as
well
aromatic
groups
participate
migrating
groups,
yielding
variety
α,α-disubstituted
ketones.
The
reaction
proceeds
under
mild
conditions
and
is
compatible
with
ethers,
esters,
halides,
nitriles,
carbamates,
substituted
arenes.
operationally
simple
fully
catalytic
prescribe
1
mol
%
benzothiazinoquinoxaline
organophotocatalyst,
0.5
Co-salen,
10
lutidinium
triflate
and,
importantly,
display
reactivity
complementary
to
procedures
employing
Brønsted
acid.
showcase
utility
protocol
in
late-stage
drug
diversifications.
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(19), С. 3918 - 3941
Опубликована: Янв. 1, 2023
This
review
demonstrates
the
redox-neutral
synthetic
approaches
towards
valuable
heterocycles
such
as
isoquinolines,
indoles,
isoquinolones,
and
tetrahydroquinolines
via
high-valent
Cp*Co(
iii
)
catalysis.
Chemistry - A European Journal,
Год журнала:
2023,
Номер
29(37)
Опубликована: Апрель 19, 2023
M-HAT
isomerization
is
a
highly
reliable
method
to
access
thermodynamically
stable
alkenes
with
high
functional
group
tolerance.
However,
synthesis
of
heteroatom-substituted
by
reaction
still
underdeveloped.
Herein,
we
report
an
enamide
using
via
combination
cobalt
and
photoredox
catalysis.
This
tolerates
variety
groups
including
haloarenes,
heteroarenes,
free
hydroxy
groups,
non-protected
indoles,
drug
derivatives.
Furthermore,
this
can
isomerize
styrene
derivatives
in
good
yield
E/Z
selectivity.
ACS Catalysis,
Год журнала:
2024,
Номер
14(5), С. 3369 - 3375
Опубликована: Фев. 16, 2024
Substituted
cyclic
alcohol
is
one
of
the
pharmaceutically
essential
scaffolds.
Here,
we
report
photoredox/cobalt-catalyzed
reductive
cyclization
alkynals
using
H2O
for
catalyst
turnover.
This
method
was
applied
to
aliphatic
and
aromatic
aldehydes
five-,
six-,
seven-membered
(heterocyclic)
ring
formation
with
various
substitutions
on
alkyne
units.
H2O-added
protocol
further
developed
into
a
one-pot
transformation
from
acetals
through
in
situ
generated
aldehydes,
which
shortened
synthetic
path
reaction.
European Journal of Organic Chemistry,
Год журнала:
2023,
Номер
26(45)
Опубликована: Окт. 16, 2023
Abstract
The
addition
of
carbon
electrophiles
to
carbonyls
and
imines
has
emerged
as
a
valuable
strategy
for
the
construction
C−C
bonds.
merger
this
concept
with
sustainable
cobalt
catalysis
yielded
numerous
innovative
methodologies.
Remarkable
functional
group
tolerance
selectivity
have
been
observed
in
many
cases,
providing
reliable
methods
bond
construction.
cobalt‐catalyzed
additions
carbonyls,
carboxylic
acid
derivatives
described
review
include
earliest
reports,
such
Takai‐Utimoto
Co/Cr
co‐catalyzed
their
progression,
well
modern
variants,
exemplified
by
recent
Co/photoredox
protocols.
systematic
appraisal
provides
clearer
perspective
inspiration
its
further
development.
ACS Catalysis,
Год журнала:
2024,
Номер
14(3), С. 2049 - 2057
Опубликована: Янв. 23, 2024
Transition-metal-catalyzed
C(sp3)–H
functionalization
has
been
much
less
investigated
compared
to
C(sp2)–H
because
the
site-selectivity
control
in
bond
activation
is
more
challenging
than
that
activation.
Site-selective
without
assistance
of
directing
groups
highly
desirable,
installation
and
removal
are
not
required.
Hence,
cycloaddition
through
a
site-selective
C–H
triggered
by
formation
metallacycles,
such
as
metalloles,
atom-
step-economical
method
for
synthesizing
complex
carbo-
heterocycles
from
simple
unsaturated
substrates.
Herein,
we
report
cobalt/photoredox
dual-catalysis-enabled
cyclization
1,5,10-enediynes
via
remote
metallole
formation,
affording
axially
chiral
aryl
alkenes.
Several
experiments
theoretical
calculations
suggest
cleavage
proceeds
σ-complex-assisted
metathesis
(σ-CAM)
intermediate.
Organic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(7), С. 2095 - 2101
Опубликована: Янв. 1, 2024
A
mild
and
efficient
visible-light
promoted
FeCl
3
-catalyzed
reductive
transamidation
of
N
-acyl
benzotriazoles
with
nitro
compounds
by
PhSiH
was
developed.
Herein,
we
report
a
visible-light-driven
and
cobalt-mediated
1,4-hydroamination
reaction
of
1,3-dienes
with
arylmines
as
the
nucleophiles.
The
involves
regioselective
addition
[CoIII]–H
to
1,3-diene,
followed
by
oxidation
nucleophilic
substitution
amines.
Using
Ir(ppy)3
photocatalyst
enables
cobalt
redox
cycle
be
implemented
without
using
an
external
oxidant
hydride
regent.
This
protocol
can
applied
well
forge
carbon–oxygen
carbon–sulfur
bonds
in
analogous
way.
