Journal of the American Chemical Society,
Journal Year:
2020,
Volume and Issue:
142(29), P. 12708 - 12714
Published: June 22, 2020
A
completely
new
route
was
established
to
synthesize
valuable
primary
amines
from
alkenes
by
using
aqueous
ammonia,
that
is,
a
simple
photocatalytic
hydroamination
of
ammonia
with
metal-loaded
TiO2
photocatalyst.
Although
the
photochemical
prefers
form
according
Markovnikov
rule,
gives
anti-Markovnikov
products
predominantly.
With
an
Au-loaded
photocatalyst,
amine
yield
reached
up
93%
and
regioselectivity
above
98%.
The
reaction
mechanism
proposed
for
hydroamination.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(3), P. 591 - 596
Published: Jan. 12, 2024
In
the
presence
of
a
thiyl
radical
species,
catalytic
Markovnikov
thiol–ene
reaction
is
challenging
because
it
prefers
to
proceed
via
pathway,
thereby
leading
anti-Markovnikov
selectivity.
this
work,
rare
example
engaged
in
enabled
by
cobalt
catalysis
reported.
This
protocol
features
avoidance
unique
oxidants,
exclusive
regioselectivity,
and
broad
substrate
scope.
Scalable
synthesis
late-stage
modification
complex
molecules
demonstrate
practicability
protocol.
ACS Catalysis,
Journal Year:
2020,
Volume and Issue:
10(9), P. 4983 - 4989
Published: April 9, 2020
A
general
protocol
has
been
developed
for
the
Markovnikov-selective
intermolecular
hydrofunctionalization
based
on
visible-light-mediated
Co/Ru
dual
catalysis.
The
key
feature
involves
photochemical
oxidation
of
an
organocobalt(III)
intermediate
derived
from
hydrogen
atom
transfer,
which
is
supported
by
electrochemical
analysis,
quenching
studies,
and
stoichiometric
experiments.
This
redox
process
enables
efficient
branch-selective
alkylation
pharmaceutically
important
nucleophiles
(phenols,
sulfonamides,
various
N-heterocycles)
using
a
wide
range
alkenes
including
moderately
electron-deficient
ones.
Moreover,
light-gated
polar
functionalization
via
organocobalt
species
was
demonstrated.
Journal of the American Chemical Society,
Journal Year:
2020,
Volume and Issue:
142(34), P. 14455 - 14460
Published: Aug. 9, 2020
Here,
we
reported
for
the
first
time
a
mechanistically
distinctive
cobalt-catalyzed
Markovnikov-type
sequential
semihydrogenation/hydrohydrazidation
of
aliphatic
terminal
alkynes
in
one
pot.
A
cobalt
hydride
species
was
employed
as
two
roles
both
unique
metal-catalyzed
insertion
and
then
hydrogen
atom
transfer
alkenes.
This
operationally
simple
protocol
exhibits
excellent
functional
group
tolerance
step
economy.
The
hydrazone
products
could
be
easily
transferred
to
various
valuable
amine
derivatives.
Nature Communications,
Journal Year:
2021,
Volume and Issue:
12(1)
Published: May 5, 2021
α-Tertiary
amides
are
of
great
importance
for
medicinal
chemistry.
However,
they
often
challenging
to
access
through
conventional
methods
due
reactivity
and
chemoselectivity
issues.
Here,
we
report
a
single-step
approach
towards
such
via
cobalt-catalyzed
intermolecular
oxidative
hydroamidation
unactivated
alkenes,
using
nitriles
either
solvent-
or
reagent-quantities.
This
protocol
is
selective
terminal
alkenes
over
groups
that
rapidly
react
under
known
carbocation
amidation
conditions
as
tertiary
alcohols,
electron-rich
ketals,
weak
C-H
bonds,
carboxylic
acids.
Straightforward
diverse
array
hindered
demonstrated,
including
rapid
synthesis
an
aminoadamantane-derived
pharmaceutical
intermediate.
Journal of the American Chemical Society,
Journal Year:
2020,
Volume and Issue:
142(29), P. 12708 - 12714
Published: June 22, 2020
A
completely
new
route
was
established
to
synthesize
valuable
primary
amines
from
alkenes
by
using
aqueous
ammonia,
that
is,
a
simple
photocatalytic
hydroamination
of
ammonia
with
metal-loaded
TiO2
photocatalyst.
Although
the
photochemical
prefers
form
according
Markovnikov
rule,
gives
anti-Markovnikov
products
predominantly.
With
an
Au-loaded
photocatalyst,
amine
yield
reached
up
93%
and
regioselectivity
above
98%.
The
reaction
mechanism
proposed
for
hydroamination.
