Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 5, 2025
The
regio-
and
stereoselective
hydroalkynylation
of
internal
alkynes
with
terminal
is
great
interest
importance
as
a
straightforward
route
for
synthesizing
multisubstituted
1,3-enynes.
However,
this
transformation
often
suffers
from
stereoselectivity
issues
when
working
unsymmetrical
alkynes.
Herein,
we
report
the
first
time
syn-stereoselective
variety
heteroatom-functionalized
including
homopropargyl
ethers,
thioethers,
tertiary
amines
by
half-sandwich
rare-earth
catalysts.
This
protocol
provides
an
atom-efficient
synthesis
new
family
heteroatom
(O,
S,
or
N)-functionalized
1,3-enynes,
featuring
100%
atom-efficiency,
broad
substrate
scope,
high
syn-stereoselectivity
(>19:1
r.r.
>19:1
syn/anti).
mechanistic
details
have
been
elucidated
deuterium-labeling
experiments,
control
isolation
transformations
key
reaction
intermediates,
revealing
that
proceeded
through
C(sp)–H
deprotonation
alkyne
scandium
alkyl
species
to
form
catalytically
active
dimeric
tetraalkynyl
followed
heteroatom-assisted
insertion
into
Sc–alkynyl
bond
subsequent
protonolysis
resulting
Sc–alkenyl
another
molecule.
coordination
N)
catalyst
metal
center
plays
critically
important
role
in
achieving
level
reactivity
stereoselectivity.
Remarkably,
can
be
recovered
reused,
constituting
example
recyclable
system
Organic Letters,
Год журнала:
2023,
Номер
25(10), С. 1622 - 1627
Опубликована: Март 3, 2023
A
cascade
oxidative
annulation
reaction
of
heterocyclic
ketene
aminals
(HKAs)
with
internal
alkynes
catalyzed
by
[Cp*RhCl2]2
and
oxidized
Cu(OAc)2·H2O
was
developed
to
efficiently
synthesize
highly
functionalized
benzo[de]chromene
derivatives
in
good
excellent
yields.
The
proceeded
the
sequential
cleavage
C(sp2)-H/O-H
C(sp2)-H/C(sp2)-H
bonds.
These
multicomponent
reactions
were
regioselective.
In
addition,
all
products
exhibited
intense
fluorescence
emission
solid
state,
they
demonstrated
concentration-dependent
quenching
presence
Fe3+,
indicating
that
these
compounds
could
be
used
recognition
Fe3+.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(5), С. 3483 - 3491
Опубликована: Янв. 24, 2024
Planar
chiral
ferrocenyl
phosphines
have
been
employed
as
highly
valuable
ligands
in
metal-catalyzed
asymmetric
reactions.
However,
their
preparation
remains
a
formidable
challenge
due
to
the
requirement
for
intricate,
multistep
synthetic
sequences.
In
addressing
this
issue,
we
developed
groundbreaking
enantioselective
C-H
activation
strategy
facilitated
by
P(III)
directing
groups,
enabling
efficient
construction
of
planar
single
step.
Our
innovative
approach
entails
combination
palladium
catalyst,
parent
phosphine,
and
phosphoramidite
ligand,
leading
exceptional
reactivity
enantioselectivity.
Remarkably,
these
novel
exhibit
remarkable
efficacy
silver-catalyzed
1,3-dipolar
cycloadditions.
We
carried
out
experimental
computational
studies
obtain
more
comprehensive
understanding
reaction
pathway
factors
contributing
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 5, 2025
The
regio-
and
stereoselective
hydroalkynylation
of
internal
alkynes
with
terminal
is
great
interest
importance
as
a
straightforward
route
for
synthesizing
multisubstituted
1,3-enynes.
However,
this
transformation
often
suffers
from
stereoselectivity
issues
when
working
unsymmetrical
alkynes.
Herein,
we
report
the
first
time
syn-stereoselective
variety
heteroatom-functionalized
including
homopropargyl
ethers,
thioethers,
tertiary
amines
by
half-sandwich
rare-earth
catalysts.
This
protocol
provides
an
atom-efficient
synthesis
new
family
heteroatom
(O,
S,
or
N)-functionalized
1,3-enynes,
featuring
100%
atom-efficiency,
broad
substrate
scope,
high
syn-stereoselectivity
(>19:1
r.r.
>19:1
syn/anti).
mechanistic
details
have
been
elucidated
deuterium-labeling
experiments,
control
isolation
transformations
key
reaction
intermediates,
revealing
that
proceeded
through
C(sp)–H
deprotonation
alkyne
scandium
alkyl
species
to
form
catalytically
active
dimeric
tetraalkynyl
followed
heteroatom-assisted
insertion
into
Sc–alkynyl
bond
subsequent
protonolysis
resulting
Sc–alkenyl
another
molecule.
coordination
N)
catalyst
metal
center
plays
critically
important
role
in
achieving
level
reactivity
stereoselectivity.
Remarkably,
can
be
recovered
reused,
constituting
example
recyclable
system
