Angewandte Chemie,
Год журнала:
2023,
Номер
135(35)
Опубликована: Май 25, 2023
Abstract
Ein
neuer
Ansatz
für
eine
hoch
enantioselektive
Halogenbrückenbindungs‐Katalyse
wurde
entwickelt.
Um
die
intrinsischen
Probleme
der
Halogenbrückenbindungen
(XB)
und
daraus
resultierenden
ungelösten
Limitierungen
in
asymmetrischen
Katalyse
zu
umgehen,
wurden
fein
justierte
Halogen–Halogen
Interaktionen
zwischen
dem
Substrat
XB‐Donor
designt,
um
das
im
Katalysatorhohlraum
vorzuorganisieren
Kontrolle
über
Enantioselektivität
verbessern.
Bei
vorliegenden
Strategie
sowohl
Elektronenwolke
(Lewis
basische
Stelle)
als
auch
sigma
(σ)‐Loch
Stelle
des
Halogen‐substituenten
Substrate
genutzt,
einen
engen
chiralen
Katalysator–Substrat–Gegenanion
Komplex
bilden.
Dies
ermöglicht
kontrollierte
Einführung
eines
hohen
Chiralitätstransfers.
Bemerkenswerte
Enantioselektivitäten
von
bis
95
:
5
e.r.
(90
%
ee
)
erreicht
einer
Modell‐Dearomatisierungsreaktion
halogensubstituierten
(Iso)chinolinen
mit
mehrzähnigen
anionen‐bindenden
Tetrakis‐Iodotriazol
Katalysatoren.
Chemical Reviews,
Год журнала:
2024,
Номер
124(3), С. 1122 - 1246
Опубликована: Янв. 2, 2024
Dearomatization
reactions
have
become
fundamental
chemical
transformations
in
organic
synthesis
since
they
allow
for
the
generation
of
three-dimensional
complexity
from
two-dimensional
precursors,
bridging
arene
feedstocks
with
alicyclic
structures.
When
those
processes
are
applied
to
pyridines,
quinolines,
and
isoquinolines,
partially
or
fully
saturated
nitrogen
heterocycles
formed,
which
among
most
significant
structural
components
pharmaceuticals
natural
products.
The
inherent
challenge
lies
low
reactivity
heteroaromatic
substrates,
makes
dearomatization
process
thermodynamically
unfavorable.
Usually,
connecting
event
irreversible
formation
a
strong
C–C,
C–H,
C–heteroatom
bond
compensates
energy
required
disrupt
aromaticity.
This
aromaticity
breakup
normally
results
1,2-
1,4-functionalization
heterocycle.
Moreover,
combination
these
subsequent
tandem
stepwise
protocols
allows
multiple
heterocycle
functionalizations,
giving
access
complex
molecular
skeletons.
aim
this
review,
covers
period
2016
2022,
is
update
state
art
nucleophilic
dearomatizations
showing
extraordinary
ability
dearomative
methodology
indicating
their
limitations
future
trends.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(35)
Опубликована: Май 25, 2023
A
new
approach
towards
highly
enantioselective
halogen-bonding
catalysis
has
been
developed.
To
circumvent
the
intrinsic
issues
of
nature
halogen-bond
(XB)
and
resultant
unresolved
limitations
in
asymmetric
catalysis,
fine-tuned
halogen-halogen
interactions
between
substrate
XB-donor
were
designed
to
preorganize
catalyst's
cavity
boost
enantiocontrol.
The
present
strategy
exploits
both
electron
cloud
(Lewis
base
site)
sigma
(σ)-hole
site
halogen
substituent
substrates
form
a
tight
catalyst-substrate-counteranion
chiral
complex,
thus
enabling
controlled
induction
high
levels
chirality
transfer.
Remarkable
enantioselectivities
up
95
:
5
e.r.
(90
%
ee)
have
achieved
model
dearomatization
reaction
halogen-substituted
(iso)quinolines
with
tetrakis-iodotriazole
multidentate
anion-binding
catalysts.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(33), С. 23457 - 23466
Опубликована: Июль 12, 2024
Developing
novel
strategies
for
catalytic
asymmetric
dearomatization
(CADA)
reactions
is
highly
valuable.
Visible
light-mediated
photocatalysis
demonstrated
to
be
a
powerful
tool
activate
aromatic
compounds
further
synthetic
transformations.
Herein,
dearomative
[2
+
2]
photocycloaddition/ring-expansion
sequence
of
indoles
with
simple
alkenes
was
reported,
providing
facile
access
enantioenriched
cyclopenta[
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(25), С. 16982 - 16989
Опубликована: Июнь 13, 2024
Catalytic
asymmetric
dearomatization
(CADA)
reactions
have
evolved
into
an
efficient
strategy
for
accessing
chiral
polycyclic
and
spirocyclic
scaffolds
from
readily
available
planar
aromatics.
Despite
the
significant
developments,
CADA
reaction
of
naphthalenes
remains
underdeveloped.
Herein,
we
report
a
Gd(III)-catalyzed
naphthalene
with
PyBox
ligand
via
visible-light-enabled
[4
+
2]
cycloaddition.
This
features
application
Gd/PyBox
complex,
which
regulates
reactivity
selectivity
simultaneously,
in
excited-state
catalysis.
A
wide
range
functional
groups
is
compatible
this
protocol,
giving
highly
enantioenriched
bridged
polycycles
excellent
yields
(up
to
96%)
>20:1
chemoselectivity,
dr,
>99%
ee).
The
synthetic
utility
demonstrated
by
2
mmol
scale
reaction,
removal
directing
group,
diversifications
products.
Preliminary
mechanistic
experiments
are
performed
elucidate
mechanism.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 28, 2025
The
cycloaddition
reactions
of
bicyclo[1.1.0]butanes
with
alkenes,
imines,
nitrones,
or
aziridines
have
served
as
an
efficient
platform
to
create
conformationally
restricted
saturated
bicyclic
scaffolds.
However,
the
use
readily
available
aromatics
in
such
reactions,
especially
asymmetric
manner,
remains
underexplored.
Herein,
we
report
a
highly
regio-
and
enantioselective
dearomative
[2π
+
2σ]
photocycloaddition
reaction
between
naphthalene
derivatives
bicyclo[1.1.0]butanes,
enabled
by
Gd(III)
catalysis.
Bicyclo[1.1.0]butanes
naphthalenes
adorned
diverse
array
functional
groups
are
well-tolerated
under
mild
conditions,
affording
enantioenriched
pharmaceutically
important
bicyclo[2.1.1]hexanes
30–96%
yields
81–93%
ee
12:1
→
>20:1
rr.
synthetic
versatility
this
is
further
demonstrated
facile
removal
directing
group
derivatizations
dearomatized
product.
UV–vis
absorption
spectroscopy
studies
suggest
involvement
excited
species
process.
Accounts of Chemical Research,
Год журнала:
2024,
Номер
unknown
Опубликована: Окт. 25, 2024
ConspectusThe
development
of
supramolecular
chemistry
has
provided
a
variety
host
molecules
and
noncovalent
tools
for
boosting
catalytic
processes,
stimulating
the
emergence
advance
catalysis,
among
which
macrocyclic
cage-like
compounds
have
attracted
great
attention
due
to
their
possession
an
enzyme-mimetic
cavity
recognition
ability.
While
privileged
scaffolds
such
as
crown
ethers,
cyclodextrins,
cucurbiturils,
calixarenes,
metal-coordinated
cages
been
widely
used,
skeletons
usually
do
not
contain
directional
binding
site;
activation
mainly
rely
on
cation-associated
interactions
or
hydrophobic
effects.
In
this
context,
recent
anion
drawn
our
developing
recognition-directed
approach
by
using
tailor-made
functionalized
macrocycles
cages.
Anions
are
important
existing
species
in
both
biological
chemical
systems
play
role
regulating
structure
function
enzymes.
We
envisioned
that
taking
advantage
anions,
including
rich
variety,
diverse
geometry,
multiple
interaction
sites,
sophisticated
cooperation
can
be
manipulated
confined
directing
efficient
selective
catalysis.Following
concept,
we
initiated
study
introducing
typical
thiourea
H-bonding
groups
design
synthesize
series
bis-thiourea
macrocycles,
especially
chiral
incorporating
linkers.
Taking
obtained
strong,
cooperative
binding,
macrocycle-enabled
counteranion
trapping
strategy
was
developed,
afforded
greatly
enhanced
efficiency
excellent
stereocontrol
acid-catalyzing
reactions.
Furthermore,
inspired
sulfate-induced
dimerization
assembly,
built
substrate-induced
assembly
system,
enabling
induced-fit
network
enantioselective
catalysis.
addition,
recognition-driven
chirality
gearing
with
more
trithiourea
cage
revealed,
could
provide
basis
implementing
anion-triggered
allosteric
catalysis
within
induced
helical
space.
Not
limited
hydrogen
bonding,
emerging
anion-π
were
largely
exploited.
A
triazine-based
prism
containing
three
V-shaped
electron-deficient
π-cavities
constructed,
properties
studied.
Based
established
driving
highly
paved
way
push
toward
practical
useful
catalyst
design.These
results
demonstrated
anion-recognition
direction
serve
powerful,
versatile
It
is
feasible
only
employing
exogenous
anions
(e.g.,
counteranion)
handle
but
also
regulation
anionic
active
intermediates/transition
states,
from
use
conventional
recognition.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(5), С. 2916 - 2925
Опубликована: Фев. 19, 2024
Sulfonium,
selenonium,
telluronium,
and
iodonium
cyanoborohydrides
have
been
synthesized,
isolated,
fully
characterized
by
various
methods,
including
single-crystal
X-ray
diffraction
(XRD)
analysis.
The
quantum
theory
of
atoms
in
molecules'
analysis
based
on
the
XRD
data
indicated
that
hydride···σ-hole
short
contacts
observed
crystal
structures
each
compound
a
purely
noncovalent
nature.
telluronium
provide
significantly
higher
rate
model
reaction
imine
hydrogenation
compared
with
sodium
tetrabutylammonium
cyanoborohydrides.
Based
NMR
high-resolution
electrospray
ionization
mass
spectrometry
indicating
progress
is
accompanied
cation
reduction,
mechanism
involving
intermediate
formation
elusive
onium
hydrides
has
proposed
as
an
alternative
to
conventional
electrophilic
activation
moiety
its
ligation
cation's
σ-hole.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Июнь 19, 2024
Abstract
In
this
study,
we
unveil
a
novel
method
for
the
asymmetric
dearomatization
of
indoles
under
cobalt/photoredox
catalysis.
By
strategically
activating
C−H
bonds
amides
and
subsequent
migratory
insertion
π‐bonds
present
in
indole
as
reactive
partner,
achieve
syn
‐selective
tetrahydro‐5
H
‐indolo[2,3‐
c
]isoquinolin‐5‐one
derivatives
with
excellent
yields
enantiomeric
excesses
up
to
>99
%.
The
developed
operates
without
metal
oxidant,
relying
solely
on
oxygen
oxidant
employing
an
organic
dye
photocatalyst
irradiation.
Control
experiments
stoichiometric
studies
elucidate
reversible
nature
enantiodetermining
activation
step,
albeit
not
being
rate‐determining.
This
study
only
expands
horizon
cobalt‐catalyzed
bond
functionalization,
but
also
showcases
potential
synergy
between
cobalt
photoredox
catalysis
enabling
synthesis
complex
molecules.
Abstract
Catalytic
asymmetric
dearomatization
reactions
represent
a
versatile
platform
for
constructing
complex
optically
active
three-dimensional
molecules.
We
present
visible-light-induced
dearomative
[2+2]
cycloaddition/ring-expansion
reaction
of
indole
derivatives
with
simple
alkenes
in
the
presence
chiral
N,N′-dioxide/terbium
complex.
This
strategy
provides
access
to
range
valuable
cyclopenta[b]indoles,
and
its
synthetic
potential
is
further
showcased
through
gram-scale
synthesis,
bioactivity
against
human
breast
cancer,
transformation
into
yuehchukene
analogue.
A
series
control
spectral
experiments,
as
well
DFT
calculations,
provide
compelling
evidence
elucidate
mechanism.
Chemical Communications,
Год журнала:
2023,
Номер
59(50), С. 7831 - 7834
Опубликована: Янв. 1, 2023
Copper-catalyzed
asymmetric
dearomative
azidation
of
tryptamines
using
azidobenziodoxolone
as
an
azidating
reagent
was
developed,
which
affords
a
variety
3a-azido-pyrroloindolines
in
good
to
high
enantioselectivities
under
mild
reaction
conditions.
The
azides
could
be
readily
transformed
into
the
corresponding
3a-amino-pyrroloindolines
via
reduction
and
1,2,3-triazole
derivatives
click
reaction.