Imidazo[1,2-
a
]pyridines
are
privileged
heterocycles
with
diverse
applications
in
medicinal
chemistry;
however,
the
catalytic
asymmetric
synthesis
of
these
heterocyclic
structures
remains
underexplored.
Herein,
we
present
an
efficient
and
modular
approach
for
atroposelective
axially
chiral
imidazo[1,2-
via
multicomponent
reaction.
By
utilizing
phosphoric
acid
catalyst,
Groebke-Blackburn-Bienaymé
reaction
involving
various
6-aryl-2-aminopyridines,
aldehydes,
isocyanides
gave
access
to
wide
range
]pyridine
atropoisomers
high
excellent
yields
enantioselectivities.
Extensive
control
experiments
underscored
pivotal
role
remote
hydrogen
bonding
donor
on
substrates
achieving
stereoselectivity
reactions.
The
versatile
derivatizations
atropisomeric
products,
especially
their
as
analog
NOBINs
facile
conversion
into
unique
6,6-spirocyclic
further
emphasize
merits
this
methodology.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(30)
Опубликована: Май 15, 2024
Atropisomers
hold
significant
fascination,
not
only
for
their
prevalence
in
natural
compounds
but
also
biological
importance
and
wide-ranging
applications
as
chiral
materials,
ligands,
organocatalysts.
While
biaryl
heterobiaryl
atropisomers
are
commonly
studied,
the
enantioselective
synthesis
of
less
abundant
heteroatom-linked
non-biaryl
presents
a
formidable
challenge
modern
organic
synthesis.
Unlike
classical
atropisomers,
these
molecules
allow
rotation
around
two
bonds,
resulting
low
barriers
to
enantiomerization
through
concerted
bond
rotations.
In
recent
years
discovery
new
configurationally
stable
rare
scaffolds
such
aryl
amines,
ethers
sulfones
well
innovative
methodologies
control
configuration
have
been
disclosed
literature
constitute
topic
this
minireview.
European Journal of Organic Chemistry,
Год журнала:
2024,
Номер
27(28)
Опубликована: Май 16, 2024
Abstract
Axially
chiral
biaryl
scaffolds
are
important
in
pharmaceuticals,
natural
products,
and
asymmetric
synthesis.
Atroposelective
ring‐opening
of
configurationally
labile
reagents
via
dynamic
kinetic
transformation
provides
a
valuable
approach
to
access
axially
atropisomers.
This
review
summarizes
seminal
contributions
recent
advancements
on
this
topic
based
the
use
different
types
reagents.
Chinese Journal of Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 7, 2025
Comprehensive
Summary
Planar‐chiral
cyclophanes
with
carbon‐centered
chirality
are
important
targets
in
natural
products
and
pharmaceuticals.
However,
synthesizing
such
planar
chiral
two
stereogenic
elements
via
a
one‐step
asymmetric
reaction
remains
formidable
challenge.
Herein,
we
present
an
efficient
kinetic
resolution
method
for
planar‐chiral
[
n
]cyclophanes
chirality.
This
is
achieved
through
the
enantioselective
allylation
of
racemic
aldehyde
catalyzed
by
Bi(OAc)
3
phosphoric
acid.
The
delivers
multiple
high
yields
excellent
enantioselectivities,
showcasing
remarkable
efficiency
(
s
factor
up
to
292).
broad
substrate
scope,
scalability,
potential
derivatization
highlight
value
this
methodology.
DFT
calculations
have
also
been
performed
provide
insights
into
origin
experimentally
observed
diastereo‐
enantioselectivity
reaction.
ACS Catalysis,
Год журнала:
2025,
Номер
unknown, С. 5211 - 5218
Опубликована: Март 12, 2025
The
asymmetric
electrophilic
amination
using
azodicarboxylates
as
the
N-source
for
construction
of
C–N
bond
has
attracted
much
attention
over
past
decades.
However,
use
in
situ
formed
nucleophilic
intermediates,
rather
than
bench-stable
reagents,
remains
elusive
and
challenging.
Herein,
we
disclose
an
enantioselective
reaction
generated
alkylgold
species
with
under
a
gold
complex
chiral
quinine-derived
squaramide
(QN-SQA)
synergetic
catalysis,
leading
to
alkylideneoxazolines
nitrogen-containing
tertiary
carbon
stereocenter
good
high
yields
enantioselectivities.
Moreover,
starting
from
same
oxazoles
incorporating
aminomethyl
group
on
5-position
could
be
obtained
by
Brønsted
acid
relay
catalysis
via
alkylideneoxazoline
species.
This
method
offers
complementary
approach
through
interception
With
this
strategic
protocol,
further
synthetic
applications
can
envisioned
catalytic
C–C
C–X
bonds.
Abstract
The
catalytic
asymmetric
Friedel–Crafts
reactions
of
(hetero)arenes
represent
a
cornerstone
in
synthetic
chemistry
due
to
their
ability
efficiently
incorporate
aromatic
rings
into
complex
molecular
architectures.
This
account
presents
comprehensive
overview
recent
advancements
the
enantioselective
(hetero)arenes,
with
particular
focus
on
that
facilitate
introduction
multiple
C–C
bonds
via
iranium/irenium-ion-triggered
electrophilic
processes.
We
examine
detail
strategies
and
methodologies
employed
achieve
stereoselective
incorporation
unsaturated
bonds,
highlighting
construction
diverse
structural
scaffolds.
Additionally,
this
showcases
broad
range
applications
powerful
transformation
organic
synthesis.
1
Introduction
2
Catalytic
Enantioselective
Reactions
Thiiranium/Thiirenium
Ions
2.1
Arylthiiranium/Arylthiirenium-Ion-Triggered
2.2
Trifluoromethylthiiranium/Trifluoromethylthiirenium-Ion-Triggered
3
Haliranium
3.1
Chloriranium-Ion-Triggered
3.2
Bromiranium-Ion-Triggered
3.3
Iodiranium-Ion-Triggered
Asymmetric
Oxidative
Arylation
Alkenes
4
Conclusion
Outlook
A
rhodium(III)-catalyzed
dual-ring
formation
via
cascade
C-H
activation/[4
+
2]
annulation
of
3,5-diaryoxadiazoles
with
alkynes
was
developed.
This
strategy
has
been
demonstrated
a
variety
3,5-diaryloxadiazoles
and
alkynes,
it
successfully
scaled
up
to
gram-scale
synthesis,
highlighting
its
potential
significance
in
the
direct
construction
C-N
atropisomers.
Furthermore,
cleavage
N-O
bond
is
essential
for
bicyclic
structure
absence
an
external
oxidant.
Mechanistic
studies
revealed
that
at
3-phenyl
group
oxadiazole
likely
rate-determining
step
this
reaction.
Nature Communications,
Год журнала:
2025,
Номер
16(1)
Опубликована: Апрель 26, 2025
Inherently
chiral
calix[4]arenes
represent
a
distinct
class
of
frameworks
whose
chirality
arises
from
the
dissymmetry
entire
molecule.
Although
these
scaffolds
have
been
widely
applied
in
various
research
fields,
their
catalytic
enantioselective
synthesis
remains
largely
underexplored.
Herein,
we
report
inherently
using
an
organocatalyzed
desymmetrization
method.
By
phosphoric
acid
catalysis,
asymmetric
electrophilic
amination
reactions
phenol-containing
prochiral
led
to
range
with
high
yields
and
enantioselectivities.
Significantly,
practicability
this
method
is
underscored
by
its
successful
implementation
as
little
0.05
mol%
catalyst,
without
compromising
reaction
efficiency
enantioselectivity.
Moreover,
aminophenol
moiety
products
could
be
easily
modified
produce
unique
diverse
N,O-heterocycles,
well
simple
meta-amino-substituted
calix[4]arene,
which
shown
promising
potential
development
new
catalysts.
Advanced Science,
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 16, 2024
Axially
chiral
diaryl
ethers
represent
a
distinct
class
of
atropisomers,
characterized
by
unique
dual
C─O
axes
system,
which
have
been
found
in
variety
natural
products,
pharmaceuticals,
and
ligands.
However,
the
catalytic
enantioselective
synthesis
these
atropoisomers
poses
significant
challenges,
due
to
difficulty
controlling
both
axes,
their
more
flexible
conformations.
Herein,
an
efficient
protocol
for
axially
is
presented
using
organocatalyzed
asymmetric
Povarov
reaction-enabled
desymmetrization,
followed
aromatizations.
This
method
yields
wide
range
novel
quinoline-based
ether
good
high
enantioselectivities.
Notably,
various
aromatization
protocols
are
developed,
resulting
diverse
set
polysubstituted
quinoline-containing
atropisomers.
Thermal
racemization
studies
suggested
excellent
configurational
stabilities
atropisomers
(with
barriers
up
38.1
kcal
mol
Chemical Communications,
Год журнала:
2024,
Номер
60(54), С. 6837 - 6846
Опубликована: Янв. 1, 2024
Axially
chiral
biaryl
ethers
and
related
compounds
hold
valuable
potential
in
natural
products,
medicinal
chemistry,
catalysis;
however,
their
asymmetric
syntheses
have
always
been
overlooked
compared
to
other
biaryl/hetero-biaryl
atropisomers.
Unlike
the
later
class
molecules
bearing
a
single
axis,
former
category
possesses
unique
type
of
atropisomerism
two
axes.
Due
great
importance
diverse
research
domains,
catalytic
atropselective
ether
synthesis
has
recently
witnessed
an
upsurge.
This
highlight
article
provides
elaborated
view
on
developments
synthetic
methods
that
explored
achieve
dual
axial
chirality
scaffolds.
Angewandte Chemie,
Год журнала:
2024,
Номер
136(30)
Опубликована: Май 15, 2024
Abstract
Atropisomers
hold
significant
fascination,
not
only
for
their
prevalence
in
natural
compounds
but
also
biological
importance
and
wide‐ranging
applications
as
chiral
materials,
ligands,
organocatalysts.
While
biaryl
heterobiaryl
atropisomers
are
commonly
studied,
the
enantioselective
synthesis
of
less
abundant
heteroatom‐linked
non‐biaryl
presents
a
formidable
challenge
modern
organic
synthesis.
Unlike
classical
atropisomers,
these
molecules
allow
rotation
around
two
bonds,
resulting
low
barriers
to
enantiomerization
through
concerted
bond
rotations.
In
recent
years
discovery
new
configurationally
stable
rare
scaffolds
such
aryl
amines,
ethers
sulfones
well
innovative
methodologies
control
configuration
have
been
disclosed
literature
constitute
topic
this
minireview.
