Palladium-catalyzed
unprecedented
atroposelective
hydrophosphination
of
internal
alkynes
has
been
realized
using
diarylphosphines,
affording
C-N
axially
chiral
trisubstituted
olefins
(vinylphosphines)
in
excellent
regioselectiviry,
(E)-selectivity,
and
enantioselectivity.
The
axial
chirality
was
established
via
integration
dynamic
kinetic
transformation
the
alkynes,
with
both
symmetrical
nonsymmetrical
secondary
phosphines
being
applicable.
In
latter
case,
additional
P-central
constructed
good
diastereoselectivity.
Advanced Synthesis & Catalysis,
Journal Year:
2023,
Volume and Issue:
365(9), P. 1398 - 1404
Published: April 12, 2023
Abstract
Herein,
we
present
a
chiral
boro‐phosphate
catalyzed
atroposelective
asymmetric
transfer
hydrogenation
method,
leading
to
family
of
axially
styrene‐type
allylalcohols.
This
dynamic
kinetic
resolution
approach
portrays
simple
procedure,
mild
conditions
and
good
enantiocontrol
(51–95%
ee),
thus
providing
an
important
alternative
assemble
the
challenging
atropisomeric
aryl‐acyclic
alkene
scaffolds.
magnified
image
Angewandte Chemie,
Journal Year:
2022,
Volume and Issue:
134(44)
Published: Sept. 15, 2022
Abstract
N−N
Atropisomers
are
a
common
motif
in
natural
products
and
represent
significant
dimension
for
exploration
modern
pharmaceutical
medicinal
chemistry.
However,
the
catalytic
atroposelective
synthesis
of
such
molecules
remains
challenging,
hampering
meaningful
development.
In
particular,
an
enantioselective
bisindole
atropisomers
is
unprecedented.
Herein,
first
via
palladium‐catalyzed
de
novo
construction
one
indole
skeleton
presented.
A
wide
variety
axially
chiral
bisindoles
were
generated
good
yields
with
excellent
enantioselectivities
cascade
condensation/N‐arylation
reaction.
Structurally
diverse
indole‐pyrrole,
indole‐carbazole,
non‐biaryl‐indole
possessing
axis
accessed
using
this
protocol.
Moreover,
investigations
density
functional
theory
(DFT)
calculations
provided
insight
into
reaction
mechanism
enantiocontrol.
Angewandte Chemie,
Journal Year:
2022,
Volume and Issue:
134(23)
Published: March 17, 2022
Abstract
Axially
chiral
styrene‐carboxylic
esters
were
synthesized
in
high
yields
with
excellent
enantioselectivity
by
the
cationic
rhodium(I)/H
8
‐BINAP
complex‐catalyzed
chelation‐controlled
[2+2+2]
cycloaddition
reactions
of
1,6‐
and
1,7‐diynes
1,3‐enyne‐carboxylic
esters.
The
diastereo‐
enantioselective
synthesis
C
2
symmetric
axially
cis
trans
‐stilbene‐dicarboxylic
was
also
achieved
double
two
molecules
1,6‐diyne
2,3‐dialkynylmaleate
2,3‐dialkynylfumarate,
respectively.
In
these
reactions,
coordinating
to
rhodium
a
five‐membered
chelate
more
reactive
than
those
six‐membered
chelate,
although
both
chelation
modes
realized
enantioselectivity.
enantioselection
mechanism
rhodium(I)‐catalyzed
elucidated
DFT
calculations.
Angewandte Chemie,
Journal Year:
2023,
Volume and Issue:
135(15)
Published: Feb. 7, 2023
Abstract
This
study
establishes
the
first
organocatalytic
enantioselective
synthesis
of
axially
chiral
N
,
N′
‐bisindoles
via
phosphoric
acid‐catalyzed
formal
(3+2)
cycloadditions
indole‐based
enaminones
as
novel
platform
molecules
with
2,3‐diketoesters,
where
de
novo
indole‐ring
formation
is
involved.
Using
this
new
strategy,
various
were
synthesized
in
good
yields
and
excellent
enantioselectivities
(up
to
87
%
yield
96
ee).
More
importantly,
class
exhibited
some
degree
cytotoxicity
toward
cancer
cells
was
derived
into
phosphine
ligands
high
catalytic
activity.
provides
a
strategy
for
using
asymmetric
organocatalysis
realize
applications
such
scaffolds
medicinal
chemistry
catalysis.
Angewandte Chemie,
Journal Year:
2022,
Volume and Issue:
134(40)
Published: Aug. 12, 2022
Abstract
Here
we
report
a
new
type
of
chiral
all‐carbon
tetrasubstituted
VQMs
generated
via
phosphoric
acids
catalyzed
nucleophilic
addition
2‐alkynylnaphthols
to
o
‐quinone
methides
or
imines,
which
can
be
captured
intramolecularly
as
result
cycloaddition
reaction.
A
class
naphthyl‐2
H
‐chromenes
bearing
axially
and
centrally
elements
quinone‐naphthols
were
prepared
efficiently
with
good
excellent
yields,
diastereoselectivities
enantioselectivities.
Noteworthy,
the
enantioselective
alkynylnaphthols
proceeded
[2+2]
cycloaddition,
followed
by
retro‐4π‐electrocyclization
6π
re‐cyclization.
While
imines
sequential
[2+4]
an
auto
oxidation
Moreover,
obtained
naphthols
converted
into
valuable
phosphine
ligands
other
functional
molecules.
Angewandte Chemie,
Journal Year:
2022,
Volume and Issue:
134(45)
Published: Sept. 16, 2022
Abstract
The
application
of
Suzuki–Miyaura
coupling
reaction
to
forge
the
atropisomeric
biaryls
has
seen
remarkable
progress
but
exploration
this
chemistry
directly
chiral
C(aryl)‐C(alkene)
axis
is
underdeveloped.
replacement
arene
substrates
by
alkenes
intensifies
challenges
in
terms
reactivity,
configurational
atropostability
product
and
selectivity
control.
By
meticulous
ligand
design
fine‐tuning
parameters,
we
identified
a
highly
active
3,3′‐triphenylsilyl‐substituted
phosphite
realize
arene‐alkene
hindered
aryl
halides
vinyl
boronates
under
very
mild
conditions.
axially
acyclic
aryl‐alkenes
were
generated
commendable
efficiency,
enantioselectivity
E
/
Z
selectivity.
Enamides
are
valuable
building
blocks
in
organic
synthesis
that
give
access
to
complex
nitrogen-containing
compounds.
However,
despite
their
high
interest,
synthetic
strategies
enamides
with
carbon-centered
chirality
scarce.
Herein,
we
report
a
mild
and
robust
method
towards
novel
gamma-chiral,
trifluoromethylated
from
easily
accessible
alpha-chiral
allylic
amines
through
efficient
transfer
(up
99.5%)
excellent
yields,
diastereo-
enantioselectivities.
A
broad
diverse
scope
is
presented
tolerates
various
substituents
functional
groups.
Additionally,
multiple
transformations
were
performed
new
chiral
scaffolds.
Among
them,
protocol
for
the
E/Z
isomerization
of
presented.
Palladium-catalyzed
unprecedented
atroposelective
hydrophosphination
of
sterically
hindered
internal
alkynes
with
secondary
phosphines
has
been
realized,
affording
C-N
axially
chiral
trisubstituted
olefins
(vinylphosphines)
in
excellent
regioselectivity,
(E)-selectivity,
and
enantioselectivity.
The
axial
chirality
was
constructed
via
integration
dynamic
kinetic
transformation
the
alkynes,
both
symmetrical
nonsymmetrical
being
applicable.
Isoquinolones
are
important
structural
motifs
in
synthetic
and
medicinal
chemistry.
Reported
herein
is
highly
atroposelective
access
to
C-N
axially
chiral
isoqionolones
via
rhodium-catalyzed
C-H
activation
of
N-alkoxy
benzamides
[3+3]
annulation
with
imidoyl
sulfoxonium
ylides.
The
coupling
system
proceeded
efficiently
under
mild
redox-neutral
conditions
excellent
functional
group
tolerance
as
a
result
dynamic
kinetic
transformation
the
ylidic
reagent
(carbene
precursor).
Experimental
computational
studies
revealed
pathway
activation,
carbene
insertion,
formal
nucleophilic
substitution-cyclization
for
this
system.
In
particular,
cyclization
enantio-determining
occurs
an
unusual
-bond
metathesis
mechanism.
benzamide,
ylide,
catalyst
each
played
dual
role.
amide
functionality
acts
directing
well
electrophilic
acylating
group,
ylide
participated
nucleophile-functionalized
reagent.
Applications
representative
products
potentially
useful
ligands
have
also
been
demonstrated.
Palladium-catalyzed
unprecedented
atroposelective
hydrophosphination
of
internal
alkynes
has
been
realized
using
diarylphosphines,
affording
C-N
axially
chiral
trisubstituted
olefins
(vinylphosphines)
in
excellent
regioselectiviry,
(E)-selectivity,
and
enantioselectivity.
The
axial
chirality
was
established
via
integration
dynamic
kinetic
transformation
the
alkynes,
with
both
symmetrical
nonsymmetrical
secondary
phosphines
being
applicable.
In
latter
case,
additional
P-central
constructed
good
diastereoselectivity.
