Angewandte Chemie,
Год журнала:
2022,
Номер
134(14)
Опубликована: Янв. 21, 2022
Abstract
The
palladium‐catalyzed
silylcyanation
of
ynamides
is
described.
This
reaction
fully
regioselective,
delivering
tetrasubstituted
2‐aminoacrylonitriles
derivatives
exclusively.
Unexpectedly,
the
nature
(aryl
or
alkyl)
substituent
located
at
β‐position
ynamide
directly
controls
stereoselectivity.
tolerates
a
number
functional
groups
and
can
be
considered
as
first
general
access
to
substituted
2‐aminoacrylonitriles.
Given
singular
reactivity
observed,
computational
study
was
performed
shed
light
on
mechanism
this
intriguing
transformation.
Relying
specific
newly
installed
vinylsilane
functionality,
scope
has
been
enlarged
by
postfunctionalization.
Chemical Society Reviews,
Год журнала:
2024,
Номер
53(14), С. 7566 - 7589
Опубликована: Янв. 1, 2024
Metal-catalyzed
highly
Markovnikov-type
selective
hydrofunctionalization
of
terminal
alkynes
provides
a
straightforward
and
atom-economical
route
to
access
1,1-disubstituted
alkenes,
which
have
wide
range
applications
in
organic
synthesis.
However,
the
transformations
are
challenging
due
electronic
steric
effects
during
addition
process.
With
development
metal-catalyzed
synthesis,
different
metal
catalysts
been
developed
solve
this
challenge,
especially
for
platinum
group
catalysts.
In
perspective,
we
review
homogeneous
according
classified
element
types
as
well
reaction
mechanisms.
Future
avenues
investigation
also
presented
help
expand
exciting
field.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(47)
Опубликована: Авг. 12, 2024
Abstract
Herein,
we
disclose
the
first
report
on
gold‐catalyzed
C(sp
2
)‐CN
cross‐coupling
reaction
by
employing
a
ligand‐enabled
Au(I)/Au(III)
redox
catalysis.
This
transformation
utilizes
acetone
cyanohydrin
as
nucleophilic
cyanide
source
to
convert
simple
aryl
and
alkenyl
iodides
into
corresponding
nitriles.
Combined
experimental
computational
studies
highlighted
crucial
role
of
cationic
silver
salts
in
activating
stable
(P,N)‐AuCN
complex
towards
oxidative
addition
subsequently
generate
key
aryl‐Au(III)
complexes.
ACS Catalysis,
Год журнала:
2020,
Номер
10(21), С. 12819 - 12827
Опубликована: Окт. 19, 2020
Herein,
we
report
a
cross-electrophile
coupling
of
benzonitrile
derivatives
and
aryl
halides
with
simple
cobalt-based
catalytic
system
under
mild
conditions
to
form
biaryl
compounds.
Even
though
the
cobalt
catalyst
is
able
activate
C(sp2)–CN
bond
alone,
use
AlMe3
Lewis
acid
enhances
reactivity
benzonitriles
improves
cross-selectivity
barely
any
influence
on
functional
group
compatibility.
X-ray
structure
determination
an
original
low-valent
species
combined
stoichiometric
reactions
reveals
catalytically
active
cobalt(I)
toward
halide
partner.
On
other
hand,
experimental
insights,
including
cyclic
voltammetry
experiments,
suggest
involvement
complex
lower
oxidation
state
derivative.
Finally,
density
theory
calculations
support
proposed
mechanistic
cycle
involving
two
different
states
perform
reaction.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(14)
Опубликована: Янв. 21, 2022
The
palladium-catalyzed
silylcyanation
of
ynamides
is
described.
This
reaction
fully
regioselective,
delivering
tetrasubstituted
2-aminoacrylonitriles
derivatives
exclusively.
Unexpectedly,
the
nature
(aryl
or
alkyl)
substituent
located
at
β-position
ynamide
directly
controls
stereoselectivity.
tolerates
a
number
functional
groups
and
can
be
considered
as
first
general
access
to
substituted
2-aminoacrylonitriles.
Given
singular
reactivity
observed,
computational
study
was
performed
shed
light
on
mechanism
this
intriguing
transformation.
Relying
specific
newly
installed
vinylsilane
functionality,
scope
has
been
enlarged
by
postfunctionalization.
Angewandte Chemie,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 27, 2025
Abstract
Since
its
discovery
in
1954,
the
hydrocyanation
of
multiple
carbon‐carbon
bonds
has
emerged
as
a
powerful
strategy
for
synthesis
nitriles.
However,
elusive
control
selectivity
and
typical
reliance
on
expensive
toxic
transition
metal
(TM)
based
catalysts
significantly
hinder
utility
this
process.
Here,
we
report
an
exclusively
regioselective
unbiased
alkynes,
driven
by
base‐catalyzed
reversible
alkyne‐allene
isomerization
phosphine‐catalyzed
HCN
transfer
to
allene.
This
TM‐free,
dual‐catalytic
approach
introduces
novel
mode
via
allene
intermediate.
The
methodology
secures
cost‐effective
access
broad
range
vinyl
nitriles
(40
examples)
with
yields
up
97%
Z/E
stereoselectivity
20:1,
including
complex
natural
product
derivatives.
A
comparison
TM‐based
systems
highlighted
2500‐fold
cost
reduction,
well
elimination
troublesome
separation
regioisomers.
Mechanistic
studies
elucidated
reaction
pathway,
shedding
light
achieved
regioselectivity.
By
altering
one
catalyst
system,
demonstrated
regioselectivity
switch,
thereby
facilitating
regiodivergent
(eight
examples).
In
broader
context,
offers
foundation
developing
next
generation
TM‐free
strategies
hydrofunctionalizations
alkynes.
A
novel
and
regioselective
cyanofunctionalization-benzannulation
cascade
reaction
has
been
developed,
utilizing
tetrabutylammonium
cyanide
(TBACN)
as
a
practical
efficient
source.
This
transformation
provides
streamlined
access
to
structurally
diverse
array
of
cyano-substituted
indolizine
scaffolds,
which
are
valuable
intermediates
in
the
synthesis
nitrogen-containing
heterocycles
with
potential
pharmaceutical
applications.
The
methodology
employs
readily
available
N-propargyl
pyrrole
derivatives
starting
materials
proceeds
under
relatively
mild
conditions,
enabling
20
distinct
cyanoindolizine
derivatives.
exhibits
remarkable
regioselectivity
installation
cyano
group,
feature
that
was
not
initially
anticipated.
unexpected
outcome
elucidated
through
combination
control
experiments,
by-product
analysis,
intermediate
isolation,
shedding
light
on
underlying
mechanistic
pathway.
Furthermore,
displays
broad
substrate
scope,
demonstrating
high
functional
group
tolerance
respect
both
electronic
steric
variations
ring
propargyl
substituents.
versatility
is
further
highlighted
by
for
downstream
transformations
into
other
groups,
such
amide
moieties,
expand
synthetic
utility
obtained
scaffolds.
Importantly,
this
work
represents
first
reported
example
TBACN-mediated
benzannulation
units,
marking
significant
advancement
field
heterocyclic
chemistry.
strategy
only
route
complex
frameworks
but
also
offers
insights
opportunities
design
development
biologically
relevant
heterocycles.
Organic Letters,
Год журнала:
2023,
Номер
25(22), С. 3989 - 3994
Опубликована: Май 25, 2023
A
palladium-catalyzed
cyanation
of
aryl
dimethylsulfonium
salts
using
cheap,
nontoxic,
and
bench-stable
K4[Fe(CN)6]·3H2O
as
the
cyanating
reagent
has
been
developed.
The
reactions
proceeded
well
under
base-free
conditions
with
various
sulfonium
provided
nitrile
yields
up
to
92%.
Aryl
sulfides
can
be
transformed
nitriles
directly
via
a
one-pot
process,
protocol
is
scalable.
Density
functional
theory
calculations
were
performed
investigate
reaction
mechanism
that
involved
catalytic
cycle
involving
oxidative
addition,
ligand
exchange,
reductive
elimination,
regeneration
yield
product.
Green Synthesis and Catalysis,
Год журнала:
2021,
Номер
3(2), С. 198 - 201
Опубликована: Дек. 24, 2021
3-Thiocyanated
chromones
was
conveniently
synthesized
from
alkynyl
aryl
ketones
using
commercially
available,
inexpensive
trichloroisocyanuric
acid
(TCCA)
as
oxidant
and
NH4SCN
thiocyanato
(SCN)
source.
This
metal-free
approach
is
postulated
to
first
in
situ
generate
thiocyanogen
chloride
(Cl-SCN)
the
reaction
of
TCCA
NH4SCN,
followed
by
a
rare
efficient
electrophilic
thiocyano
oxyfunctionalization
alkynes
enabled
reactive
species
generated
thereof.
