Angewandte Chemie,
Год журнала:
2024,
Номер
136(22)
Опубликована: Март 23, 2024
Abstract
Despite
the
significance
of
chiral
allene
skeletons
in
catalysis,
organic
synthesis
and
medicinal
chemistry
et
al.,
there
is
a
scarcity
reports
on
axially
allenyl
phosphorus
compounds.
Here,
we
disclosed
an
efficient
straightforward
cascade
reaction
between
ethynyl
ketones
phosphine
oxides,
resulting
broad
array
trisubstituted
allenes
incorporating
moiety
high
yields
with
excellent
stereoselectivities
facilitated
by
peptide‐mimic
phosphonium
salt
(PPS)
Additionally,
comprehensive
series
mechanistic
experiments
have
been
conducted
to
elucidate
that
this
proceeds
via
asymmetric
Pudovik
addition
followed
subsequent
phospha
‐Brook
rearrangement
occurs
concomitantly
kinetic
resolution,
representing
stereospecific
protonation
process
facilitating
central‐to‐axial
chirality
transfer
manner.
We
anticipate
our
research
will
pave
way
for
promising
exploration
novel
stereo‐induction
pattern
addition/
reaction.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(13), С. 9241 - 9251
Опубликована: Март 19, 2024
Much
attention
has
been
focused
on
the
catalytic
asymmetric
creation
of
single
chiral
centers
or
two
adjacent
stereocenters.
However,
construction
nonadjacent
stereocenters
is
significant
importance
but
challenging
because
lack
remote
induction
models.
Herein,
based
a
C═C
bond
relay
strategy,
we
report
synergistic
Pd/Cu-catalyzed
1,5-double
model.
All
four
stereoisomers
target
products
bearing
1,5-nonadjacent
involving
both
allenyl
axial
and
central
chirality
could
be
obtained
divergently
by
simply
changing
combination
catalysts
with
different
configurations.
Control
experiments
DFT
calculations
reveal
novel
mechanism
1,5-oxidative
addition,
contra-thermodynamic
η3-allyl
palladium
shift,
conjugate
nucleophilic
substitution,
which
play
crucial
roles
in
control
reactivity,
regio-,
enantio-,
diastereoselectivity.
It
expected
that
this
strategy
may
provide
general
protocol
for
synthesis
structural
motifs
distant
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(36)
Опубликована: Июнь 19, 2023
We
describe
a
copper
catalyst
that
promotes
the
addition
of
phosphines
to
cyclopropenes
at
ambient
temperature.
A
range
cyclopropylphosphines
bearing
different
steric
and
electronic
properties
can
now
be
accessed
in
high
yields
enantioselectivities.
Enrichment
phosphorus
stereocenters
is
also
demonstrated
via
Dynamic
Kinetic
Asymmetric
Transformation
(DyKAT)
process.
combined
experimental
theoretical
mechanistic
study
supports
an
elementary
step
featuring
insertion
Cu
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(22)
Опубликована: Март 23, 2024
Abstract
Despite
the
significance
of
chiral
allene
skeletons
in
catalysis,
organic
synthesis
and
medicinal
chemistry
et
al.,
there
is
a
scarcity
reports
on
axially
allenyl
phosphorus
compounds.
Here,
we
disclosed
an
efficient
straightforward
cascade
reaction
between
ethynyl
ketones
phosphine
oxides,
resulting
broad
array
trisubstituted
allenes
incorporating
moiety
high
yields
with
excellent
stereoselectivities
facilitated
by
peptide‐mimic
phosphonium
salt
(PPS)
Additionally,
comprehensive
series
mechanistic
experiments
have
been
conducted
to
elucidate
that
this
proceeds
via
asymmetric
Pudovik
addition
followed
subsequent
phospha
‐Brook
rearrangement
occurs
concomitantly
kinetic
resolution,
representing
stereospecific
protonation
process
facilitating
central‐to‐axial
chirality
transfer
manner.
We
anticipate
our
research
will
pave
way
for
promising
exploration
novel
stereo‐induction
pattern
addition/
reaction.
Organic Letters,
Год журнала:
2024,
Номер
26(22), С. 4678 - 4683
Опубликована: Май 24, 2024
The
radical
1,4-functionalizations
of
1,3-enynes
have
emerged
as
a
powerful
strategy
for
the
synthesis
multisubstituted
allenes.
However,
phosphorus-centered
radical-initiated
transformations
remain
largely
elusive.
Herein,
visible-light
photoredox
catalytic
regioselective
hydrophosphinylation
with
diaryl
phosphine
oxides
phosphinoyl
precursors
has
been
realized.
This
protocol
features
mild
conditions,
wide
substrate
scope,
and
good
functional
group
tolerance,
producing
diverse
range
phosphinoyl-substituted
allenes
in
moderate
to
yields
high
atom
economy.
Detailed
mechanistic
experiments
revealed
radical-polar
crossover
process
reaction.
ACS Catalysis,
Год журнала:
2024,
Номер
14(13), С. 9940 - 9954
Опубликована: Июнь 19, 2024
Metal-catalyzed
allenylic
substitution
reactions
where
allenes
serve
as
electrophilic
precursors
have
been
recognized
a
rapid
way
for
novel
allene
construction.
On
the
contrary,
chemistry
in
which
act
nucleophiles
has
far
less
investigated,
especially
powerful
platform
such
metal-catalyzed
allylic
alkylation
reactions.
We
herein
describe
two
unprecedented
palladium-catalyzed
of
an
nucleophile.
In
first
reaction,
using
vinyloxazolidinones
allyl
precursor,
asymmetric
allylation
trisubstituted
allenones
worked
well
to
prepare
array
axially
chiral
tetrasubstituted
allenes.
Mechanistic
studies
and
density
functional
theory
(DFT)
calculations
indicated
that
weak
hydrogen-bonding
interaction
between
acidic
C(sp2)–H
allenone
nitrogen
anion
π-azaallyl-Pd
species
is
key
success
stereocontrol.
This
reaction
revealed
intriguing
reactivity
nucleophilic
time.
second
with
use
allenylethylene
carbonates
π-oxyallyl-Pd
precursors,
presented
unique
under
different
conditions
provide
divergent
synthetic
access
(E)-
(Z)-allenyl
diene
products.
Interestingly,
subsequent
sequential
intramolecular
cyclization/isomerization
(Z)-product
delivered
dihydrooxepine
derivatives
[5
+
2]
annulation
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(20)
Опубликована: Март 10, 2023
The
palladium-catalyzed
asymmetric
carboamination
reaction
is
one
of
the
most
significant
transformations
in
organic
chemistry.
Herein,
we
report
first
alleneamination
β,γ-unsaturated
hydrazones
with
propargylic
acetates.
This
protocol
enables
efficient
installation
various
multisubstituted
allene
groups
onto
dihydropyrazoles
good
yields
excellent
enantioselectivities.
chiral
sulfinamide
phosphine
ligand
Xu-5
exhibits
highly
stereoselective
control
this
protocol.
salient
features
include
readily
available
starting
materials,
a
broad
substrate
scope,
an
easy
scale-up,
mild
conditions
and
versatile
transformations.
Nature Communications,
Год журнала:
2023,
Номер
14(1)
Опубликована: Авг. 10, 2023
Catalytic
enantioselective
introduction
of
a
propargyl
group
constitutes
one
the
most
important
carbon-carbon
forming
reactions,
as
it
is
versatile
to
be
transformed
into
diverse
functional
groups
and
frequently
used
in
synthesis
natural
products
biologically
active
molecules.
Stereoconvergent
transformations
racemic
precursors
single
enantiomer
via
radicals
represent
powerful
strategy
provide
new
reactivity.
However,
only
few
Cu-
or
Ni-catalyzed
protocols
have
been
developed
with
limited
reaction
modes.
Herein,
photoredox/cobalt-catalyzed
regio-,
diastereo-
addition
aldehydes
presented,
enabling
construction
broad
scope
homopropargyl
alcohols
that
are
otherwise
difficult
access
high
efficiency
stereoselectivity
from
carbonates.
Mechanistic
studies
DFT
calculations
provided
evidence
for
involvement
radicals,
origin
stereoconvergent
process
stereochemical
models.