ACS Catalysis,
Journal Year:
2020,
Volume and Issue:
10(13), P. 7117 - 7122
Published: June 12, 2020
Ir(III)-catalyzed
enantioselective
C–H
activation
generally
relies
on
the
combination
of
chiral
Ir(III)
cyclopentadienyl
complexes
with
carboxylic
acids
to
ensure
high
enantiocontrol.
We
report
herein
achiral
CpxIr(III)-catalyzed
amidation
ferrocenes.
Crucial
enantioselectivity
is
use
a
acid
ligand
derived
from
tert-leucine
via
Pd(II)-catalyzed
γ-C(sp3)–H
arylation
and
sterically
more
hindered
CpxIr(III)
catalyst.
This
reaction
proceeds
smoothly
under
very
mild
conditions
(0
°C)
tolerates
wide
range
ferrocene
carboxamides
dioxazolones,
providing
products
in
good
yields
(up
97.5:2.5
er).
protocol
might
open
way
for
asymmetric
activation.
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.
Angewandte Chemie International Edition,
Journal Year:
2020,
Volume and Issue:
59(9), P. 3568 - 3572
Published: Jan. 8, 2020
A
simple
and
ubiquitously
present
group,
free
amine,
is
used
as
a
directing
group
to
synthesize
axially
chiral
biaryl
compounds
by
PdII
-catalyzed
atroposelective
C-H
olefination.
broad
range
of
biaryl-2-amines
can
be
obtained
in
good
yields
with
high
enantioselectivities
(up
97
%
ee).
Chiral
spiro
phosphoric
acid
(SPA)
proved
an
efficient
ligand
the
loading
could
reduced
1
mol
without
erosion
enantiocontrol
gram-scale
synthesis.
The
resulting
also
provide
platform
for
synthesis
set
ligands.
Journal of the American Chemical Society,
Journal Year:
2020,
Volume and Issue:
142(42), P. 18266 - 18276
Published: Oct. 8, 2020
Atropisomeric
anilides
have
received
tremendous
attention
as
a
novel
class
of
chiral
compounds
possessing
restricted
rotation
around
an
N-aryl
axis.
However,
in
sharp
contrast
to
the
well-studied
synthesis
biaryl
atropisomers,
catalytic
asymmetric
remains
daunting
challenge,
largely
due
higher
degree
rotational
freedom
compared
their
counterparts.
Here
we
describe
highly
efficient
atropisomeric
via
Pd(II)-catalyzed
atroposelective
C-H
olefination
using
readily
available
L-pyroglutamic
acid
ligand.
A
broad
range
were
prepared
high
yields
(up
99%
yield)
and
excellent
stereoinduction
>99%
ee)
under
mild
conditions.
Experimental
studies
indicated
that
atropostability
those
anilide
atropisomers
toward
racemization
relies
on
both
steric
electronic
effects.
computational
conducted
elucidate
reaction
mechanism
rate-determining
step.
DFT
calculations
revealed
amino
ligand
distortion
is
responsible
for
enantioselectivity
bond
activation
The
potent
applications
new
type
Rh(III)-catalyzed
conjugate
addition
Lewis
base
catalysts
enantioselective
allylation
aldehydes
been
demonstrated.
This
strategy
could
provide
straightforward
route
access
anilides,
one
most
challenging
types
axially
compounds.
Angewandte Chemie International Edition,
Journal Year:
2020,
Volume and Issue:
59(32), P. 13288 - 13294
Published: April 16, 2020
Abstract
Reported
herein
is
the
atroposelective
synthesis
of
biaryl
NH
isoquinolones
by
Rh
III
‐catalyzed
C−H
activation
benzamides
and
intermolecular
[4+2]
annulation
for
a
broad
scope
2‐substituted
1‐alkynylnaphthalenes,
as
well
sterically
hindered,
symmetric
diarylacetylenes.
The
axial
chirality
constructed
based
on
dynamic
kinetic
transformation
alkyne
in
redox‐neutral
with
benzamides,
insertion
being
stereodetermining.
reaction
accommodates
both
heteroaryl
carboxamides
proceeds
excellent
regioselectivity
(if
applicable)
enantioselectivities
(average
91.8
%
ee
).
An
enantiomerically
diastereomerically
pure
rhodacyclic
complex
was
prepared
offers
insight
into
enantiomeric
control
coupling
system,
wherein
steric
interactions
between
amide
directing
group
substrate
dictate
regio‐
enantioselectivity.
Organic & Biomolecular Chemistry,
Journal Year:
2020,
Volume and Issue:
18(37), P. 7291 - 7315
Published: Jan. 1, 2020
This
review
describes
recent
advances
in
C–H
functionalisation
using
transient
directing
groups.
Advances
group
design,
new
bond
forming
methodologies,
regio-
and
stereoselective
processes,
mechanistic
insights
are
discussed.
ACS Catalysis,
Journal Year:
2020,
Volume and Issue:
10(21), P. 12898 - 12919
Published: Oct. 21, 2020
Transition-metal-catalyzed
C–H
bond
functionalization
has
known
a
rapid
evolution
in
the
last
years,
offering
modern
strategies
for
reaching
high
molecular
complexity
step-
and
atom-economical
way.
Despite
indisputable
advances,
selectivity
issues
still
remain,
given
ubiquity
of
bonds
on
molecules;
thus,
several
approaches
have
been
developed
to
tackle
this
challenge.
Among
them,
use
transient
directing
group
emerged
as
an
effective
tool,
circumventing
need
extra
synthetic
steps
install
then
cleave
molecule.
More
recently,
strategy
successfully
applied
even
more
challenging
transition-metal-catalyzed
enantioselective
functionalization.
This
review
will
highlight
discuss
main
advances
made
chiral
C(sp2)–H
C(sp3)–H
by
transition-metal
catalysis.
Angewandte Chemie International Edition,
Journal Year:
2019,
Volume and Issue:
59(9), P. 3475 - 3479
Published: Dec. 23, 2019
Abstract
A
ruthenium(II)‐catalyzed
asymmetric
intramolecular
hydroarylation
assisted
by
a
chiral
transient
directing
group
has
been
developed.
series
of
2,3‐dihydrobenzofurans
bearing
all‐carbon
quaternary
stereocenters
have
prepared
in
remarkably
high
yields
(up
to
98
%)
and
enantioselectivities
>99
%
ee
).
By
this
methodology,
novel
total
synthesis
CB2
receptor
agonist
MDA7
successfully
