Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(9), P. 1886 - 1890
Published: Feb. 28, 2024
Herein,
we
introduce
an
iodonium
ylide
strategy
to
achieve
novel
α-alkylation
of
cyclic
1,3-dicarbonyls
through
harnessing
C(sp3)–Rh
species
generated
from
5-exo-trig
cyclization
provide
rapid
access
molecular
hybridization
medically
important
isoindolin-1-ones
and
readily
available
substrates.
This
approach
features
mild
conditions,
good
yield,
excellent
functional
group
tolerance,
the
simultaneous
formation
two
new
chemical
bonds
one
stereogenic
center.
Moreover,
hydroxyl
resulting
product
provides
a
handle
for
downstream
transformations.
Importantly,
also
demonstrate
this
can
be
achieved
in
one-pot
manner.
A
complex
was
prepared
proved
key
intermediate.
Chemical Society Reviews,
Journal Year:
2022,
Volume and Issue:
51(12), P. 5042 - 5100
Published: Jan. 1, 2022
Transition
metal-catalysed
direct
borylation
of
hydrocarbons
via
C–H
bond
activation
has
received
a
remarkable
level
attention
as
popular
reaction
in
the
synthesis
organoboron
compounds
owing
to
their
synthetic
versatility.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(11)
Published: Jan. 20, 2023
In
recent
years,
the
merging
of
electrosynthesis
with
3d
metal
catalyzed
C-H
activation
has
emerged
as
a
sustainable
and
powerful
technique
in
organic
synthesis.
Despite
impressive
advantages,
development
an
enantioselective
version
remains
elusive
poses
daunting
challenge.
Herein,
we
report
first
electrooxidative
cobalt-catalyzed
enantio-
regioselective
C-H/N-H
annulation
olefins
using
undivided
cell
at
room
temperature
(up
to
99
%
ee).
t
Bu-Salox,
rationally
designed
Salox
ligand
bearing
bulky
tert-butyl
group
ortho-position
phenol,
was
found
be
crucial
for
this
asymmetric
reaction.
A
strong
cooperative
effect
between
Bu-Salox
3,4,5-trichloropyridine
enabled
highly
more
challenging
α-olefins
without
secondary
bond
interactions
96
ee
97
:
3
rr).
Cyclovoltametric
studies,
preparation,
characterization,
transformation
cobaltacycle
intermediates
shed
light
on
mechanism
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(28)
Published: May 2, 2022
Abstract
Among
sulfoximine
derivatives
containing
a
chiral
sulfur
center,
benzothiadiazine‐1‐oxides
are
important
for
applications
in
medicinal
chemistry.
Here,
we
report
that
the
combination
of
an
achiral
cobalt(III)
catalyst
and
pseudo‐
C
2
‐symmetric
H
8
‐binaphthyl
carboxylic
acid
enables
asymmetric
synthesis
from
sulfoximines
dioxazolones
via
enantioselective
C−H
bond
cleavage.
With
optimized
protocol,
with
several
functional
groups
can
be
accessed
high
enantioselectivity.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(21)
Published: March 20, 2023
Metalla-electrocatalyzed
C-H
oxygenation
represents
one
of
the
most
straightforward
and
sustainable
approaches
to
access
valuable
oxygenated
molecules.
Despite
significant
advances,
development
enantioselective
electrochemical
reaction
is
very
challenging
remains
elusive.
Herein,
we
described
first
CoII
-catalyzed
alkoxylation.
A
broad
range
enantioenriched
alkoxylated
phosphinamides
were
obtained
in
good
yields
with
excellent
enantioselectivities
(up
98
%
yield
>99
ee).
An
unusual
cobalt(III)
alcohol
complex
was
prepared
fully
characterized,
which
proven
be
a
key
intermediate
this
alkoxylation
reaction.
Mechanistic
studies
revealed
that
oxidation
CoIII
CoIV
facilitated
by
base
whole
process
proceeded
through
cobalt(III/IV/II)
catalytic
cycle.
ACS Catalysis,
Journal Year:
2023,
Volume and Issue:
13(7), P. 4250 - 4260
Published: March 13, 2023
Herein,
we
disclose
an
efficient
cobalt-catalyzed
enantioselective
C–H
activation
and
annulation
of
benzamides
with
alkenes.
This
transformation
is
facilitated
via
the
commercially
available
cobalt(II)
catalyst
in
presence
easily
prepared
chiral
salicyl-oxazoline
(Salox)
ligand,
which
provides
facile
access
to
(R)
or
(S)
enantiomers
dihydroisoquinolone
derivatives.
It
noticeable
that
reaction
proceeded
efficiently
within
extremely
short
time
from
10
30
min
under
mild
conditions.
A
broad
range
alkenes
bear
various
functional
substituents
have
been
shown
good
compatibility
deliver
targeted
products
high
yields
enantioselectivities
(51
examples,
up
98%
yield
99%
ee).
The
gram
scale
experiment
removal
directing
group
further
demonstrate
practicability
this
protocol
potential
industrial
applications.
Density
theory
calculations
elucidate
mechanism,
spin-state
change
olefin
insertion
step
accelerates
subsequent
C–N
reductive
elimination,
identified
as
stereo-determining
step.
AIM
analysis
indicates
π
interactions
are
vital
for
controlling
switching
stereoselectivity.
Chemical Science,
Journal Year:
2022,
Volume and Issue:
13(9), P. 2783 - 2788
Published: Jan. 1, 2022
Despite
indisputable
progress
in
the
development
of
electrochemical
transformations,
electrocatalytic
annulations
for
synthesis
biologically
relevant
three-dimensional
spirocyclic
compounds
has
as
yet
not
been
accomplished.
In
sharp
contrast,
herein,
we
describe
palladaelectro-catalyzed
C-H
activation/[3
+
2]
spiroannulation
alkynes
by
1-aryl-2-naphthols.
Likewise,
a
cationic
rhodium(iii)
catalyst
was
shown
to
enable
electrooxidative
[3
spiroannulations
via
formal
C(sp3)-H
activations.
The
versatile
featured
broad
substrate
scope,
employing
electricity
green
oxidant
lieu
stoichiometric
chemical
oxidants
under
mild
conditions.
An
array
enones
and
diverse
spiropyrazolones,
bearing
all-carbon
quaternary
stereogenic
centers
were
thereby
accessed
user-friendly
undivided
cell
setup,
with
molecular
hydrogen
sole
byproduct.
