Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(15)
Published: Jan. 30, 2024
Abstract
The
combination
of
achiral
Cp*Rh(III)
with
chiral
carboxylic
acids
(CCAs)
represents
an
efficient
catalytic
system
in
transition
metal‐catalyzed
enantioselective
C−H
activation.
However,
this
hybrid
catalysis
is
limited
to
redox‐neutral
activation
reactions
and
the
adopt
oxidative
remains
elusive
pose
a
significant
challenge.
Herein,
we
describe
development
electrochemical
Cp*Rh(III)‐catalyzed
annulation
sulfoximines
alkynes
enabled
by
acid
(CCA)
operationally
friendly
undivided
cell
at
room
temperature.
A
broad
range
enantioenriched
1,2‐benzothiazines
are
obtained
high
yields
excellent
enantioselectivities
(up
99
%
yield
98
:
2
er).
practicality
method
demonstrated
scale‐up
reaction
batch
reactor
external
circulation.
crucial
intermediate
isolated,
characterized,
transformed,
providing
rational
support
for
Rh(III)/Rh(I)
electrocatalytic
cycle.
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
61(39)
Published: Aug. 2, 2022
The
atroposelective
synthesis
of
atropisomers
with
vicinal
diaxes
remains
rare
and
challenging,
due
to
the
steric
influence
between
two
axes
their
unique
topology.
Herein,
we
disclose
a
single-step
construction
C-C
C-N
chiral
by
cyclopentadiene
(Cp)-free
cobalt-catalyzed
intramolecular
C-H
annulation,
providing
desired
diaxial
structures
decent
stereocontrols
both
(up
>99
%
ee
70
:
1
dr).
optically
pure
products
bearing
fluorophores
show
circular
polarized
luminescence
(CPL)
properties,
being
candidate
materials
for
potential
CPL
applications.
Atropisomerization
experiments
density
function
theory
(DFT)
calculations
are
conducted
study
rotational
barriers
rotation
pathways
diaxes.
Wiley eBooks,
Journal Year:
2022,
Volume and Issue:
unknown
Published: July 6, 2022
Asymmetric
intermediateScheme
1
Different
types
of
desymmetrizations
based
on
metal-promoted
C--H
activations.4
Transition
Metal-Catalyzed
Desymmetrizations
Based
Activation
Processes
CO
2
H
R
Pd(OAc)
(5
mol%)
Boc-Ile-OH
(10
BQ
KHCO
3
(0.5
equiv)
tAmylOH,
90
°C
Ar
19
examples
35-73%
yield,
ee
up
to
97%
+
S
O
Ac-Leu-OH
(30
Ag
(2
HFIP,
75
26
31-72%
99%
(a)
(c)
P
N
Boc-Tyr(tBu)-OH
(20
BQ,
Li
(1.5
DMF/H
O,
40
F
CN
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.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(37)
Published: May 4, 2023
Abstract
Enantioselective
synthesis
of
N−N
biaryl
atropisomers
is
an
emerging
area
but
remains
underexplored.
The
development
efficient
in
great
demand.
Herein,
the
construction
through
iridium‐catalyzed
asymmetric
C−H
alkylation
reported
for
first
time.
In
presence
readily
available
Ir
precursor
and
Xyl‐BINAP,
a
variety
axially
chiral
molecules
based
on
indole‐pyrrole
skeleton
were
obtained
good
yields
(up
to
98
%)
with
excellent
enantioselectivity
99
%
ee).
addition,
bispyrrole
could
also
be
synthesized
enantioselectivity.
This
method
features
perfect
atom
economy,
wide
substrate
scope,
multifunctionalized
products
allowing
diverse
transformations.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(21)
Published: March 21, 2023
The
catalytic
asymmetric
construction
of
N-N
atropisomeric
biaryls
remains
a
formidable
challenge.
Studies
them
lag
far
behind
studies
the
more
classical
carbon-carbon
biaryl
atropisomers,
hampering
meaningful
development.
Herein,
first
palladium-catalyzed
enantioselective
C-H
activation
pyrroles
for
synthesis
atropisomers
is
presented.
Structurally
diverse
indole-pyrrole
possessing
chiral
axis
were
produced
with
good
yields
and
high
enantioselectivities
by
alkenylation,
alkynylation,
allylation,
or
arylation
reactions.
Furthermore,
kinetic
resolution
trisubstituted
heterobiaryls
sterically
demanding
substituents
was
also
achieved.
Importantly,
this
versatile
functionalization
strategy
enables
iterative
exquisite
selectivity,
expediting
formation
valuable,
complex,
atropisomers.
Chemical Reviews,
Journal Year:
2023,
Volume and Issue:
123(17), P. 10641 - 10727
Published: Aug. 28, 2023
Enantiomers,
where
chirality
arises
from
restricted
rotation
around
a
single
bond,
are
atropisomers.
Due
to
the
unique
nature
of
origins
their
chirality,
synthetic
strategies
access
these
compounds
in
an
enantioselective
manner
differ
those
used
prepare
enantioenriched
containing
point
arising
unsymmetrically
substituted
carbon
center.
In
particular
stereodynamic
transformations,
such
as
dynamic
kinetic
resolutions,
thermodynamic
and
deracemizations,
which
rely
on
ability
racemize
or
interconvert
enantiomers,
promising
set
transformations
optically
pure
late
stage
sequence.
Translation
approaches
with
atropisomers
requires
expanded
toolbox
for
epimerization/racemization
provides
opportunity
develop
new
conceptual
framework
synthesis
compounds.
