1,5-Hydrogen atom transfer of α-iminyl radical cations: a new platform for relay annulation for pyridine derivatives and axially chiral heterobiaryls
Chemical Science,
Год журнала:
2024,
Номер
15(20), С. 7502 - 7514
Опубликована: Янв. 1, 2024
The
exploitation
of
new
reactive
species
and
novel
transformation
modes
for
their
synthetic
applications
have
significantly
promoted
the
development
organic
methodology,
drug
discovery,
advanced
functional
materials.
α-Iminyl
radical
cations,
a
class
distonic
ions,
exhibit
great
potential
synthesis
valuable
molecules.
For
generation,
conjugate
addition
to
α,β-unsaturated
iminium
ions
represents
concise
yet
highly
challenging
route,
because
Язык: Английский
Photoredox Catalytic Deracemization Enabled Enantioselective and Modular Access to Axially Chiral N‐Arylquinazolinones
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 24, 2024
Visible
light-driven
photocatalytic
deracemization
is
highly
esteemed
as
an
ideal
tool
for
organic
synthesis
due
to
its
exceptional
atom
economy
and
synthetic
efficiency.
Consequently,
successful
instances
of
allenes
have
been
established,
where
the
activated
energy
photosensitizer
should
surpass
that
substrates,
representing
intrinsic
requirement.
Accordingly,
this
method
not
applicable
axially
chiral
molecules
with
significantly
high
triplet
energies.
In
study,
we
present
a
photoredox
catalytic
approach
enables
efficient
valuable
yet
challenging-to-access
2-azaarene-functionalized
quinazolinones.
The
substrate
scope
extensive,
allowing
both
3-axis
unmet
1-axis
assembly
through
facile
oxidation
diverse
central
2,3-dihydroquinazolin-4(1H)-ones
can
be
easily
prepared
achieve
enantiomer
enrichment
via
deracemization.
Mechanistic
studies
reveal
importance
selection
in
attaining
excellent
chemoselectivity
highlight
indispensability
Brønsted
acid
enabling
enantioselective
protonation
accomplish
Язык: Английский
Rational Design and Stereodivergent Construction of Enantioenriched Tetrahydro-β-Carbolines Containing Multistereogenic Centers
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(43), С. 29928 - 29942
Опубликована: Окт. 17, 2024
Chiral
tetrahydro-β-carbolines,
as
one
of
the
most
intriguing
subtypes
indole
alkaloids,
have
emerged
privileged
units
in
plenty
natural
products
and
biologically
active
molecules
with
an
impressive
range
bioactive
properties.
However,
stereodivergent
construction
these
valuable
skeletons
containing
multistereogenic
centers
from
readily
available
starting
materials
remains
very
challenging,
especially,
view
introduction
axial
chirality.
Herein,
we
developed
efficient
method
toward
enantioenriched
tetrahydro-β-carbolines
tryptophan-derived
aldimine
esters
allylic
carbonates
under
mild
reaction
conditions.
The
proceeds
a
sequential
fashion
involving
synergistic
Cu/Ir-catalyzed
allylation
Brønsted
acid-promoted
stereospecific
Pictet–Spengler
reaction,
affording
wide
chiral
bearing
up
to
four
stereogenic
good
yields
excellent
stereoselectivity
control.
When
N-aryl-substituted
were
utilized,
notably,
unique
C–N
heterobiaryl
axis
could
be
simultaneously
constructed
formation
third
point
center
last
cyclization
step
through
dynamic
kinetic
resolution
(DKR).
Computational
mechanistic
studies
established
plausible
mechanism
for
dual
asymmetric
succeeding
protonation-assisted
complete
annulation.
Structure–activity
relationship
analyses
unveil
origins
stereochemistry
building
three
centers.
Язык: Английский
Photoredox Catalytic Deracemization Enabled Enantioselective and Modular Access to Axially Chiral N‐Arylquinazolinones
Angewandte Chemie,
Год журнала:
2024,
Номер
136(43)
Опубликована: Июль 24, 2024
Abstract
Visible
light‐driven
photocatalytic
deracemization
is
highly
esteemed
as
an
ideal
tool
for
organic
synthesis
due
to
its
exceptional
atom
economy
and
synthetic
efficiency.
Consequently,
successful
instances
of
allenes
have
been
established,
where
the
activated
energy
photosensitizer
should
surpass
that
substrates,
representing
intrinsic
requirement.
Accordingly,
this
method
not
applicable
axially
chiral
molecules
with
significantly
high
triplet
energies.
In
study,
we
present
a
photoredox
catalytic
approach
enables
efficient
valuable
yet
challenging‐to‐access
2‐azaarene‐functionalized
quinazolinones.
The
substrate
scope
extensive,
allowing
both
3‐axis
unmet
1‐axis
assembly
through
facile
oxidation
diverse
central
2,3‐dihydroquinazolin‐4(1
H
)‐ones
can
be
easily
prepared
achieve
enantiomer
enrichment
via
deracemization.
Mechanistic
studies
reveal
importance
selection
in
attaining
excellent
chemoselectivity
highlight
indispensability
Brønsted
acid
enabling
enantioselective
protonation
accomplish
Язык: Английский
Rhodium-Catalyzed Regioselective [4 + 2] Cycloaddition of Ynamines and 2-(Cyanomethyl)phenylboronates
Organic Letters,
Год журнала:
2024,
Номер
26(31), С. 6586 - 6590
Опубликована: Июль 30, 2024
A
rhodium-catalyzed
[4
+
2]
cycloaddition
of
ynamines
and
2-(cyanomethyl)phenylboronates
has
been
developed,
leading
to
efficient
excellent
regioselective
synthesis
valuable
indole-linked
aromatic
compounds
in
a
concise
flexible
approach.
Interestingly,
this
strategy
was
successful
the
construction
C···N
axially
chiral
indoles
with
high
enantiocontrol
by
introduction
new
phosphoramidite
ligand
(Xie-Phos).
Язык: Английский