Organometallics,
Год журнала:
2024,
Номер
43(17), С. 1929 - 1937
Опубликована: Авг. 24, 2024
Metal-catalyzed
[2+2+2]
cyclization
reactions
are
powerful
tools
for
the
preparation
of
(hetero)aromatic
compounds.
However,
they
have
rarely
been
applied
in
ferrocene
chemistry.
We
employed
Co-catalyzed
4-ferrocenylbenzonitrile
with
α,ω-diynes
to
prepare
a
series
(4-ferrocenylphenyl)pyridines
under
solvothermal
conditions
or
using
microwave
irradiation.
The
resulting
pyridines,
anellated
by
carbocyclic
and
heteroatom-containing
rings,
were
reacted
[(η5-C5Me5)MCl2]2/NaOAc
(M
=
Rh
Ir)
produce
respective
cyclometalated
complexes
good
yields.
All
compounds
characterized
spectroscopic
methods
(NMR
ESI–MS)
cyclic
voltammetry,
structures
representative
[(η5-C5Me5)MCl(FcC6H3–C5H2N(CH2)4-κ2C,N)]
Ir;
Fc
ferrocenyl)
determined
single-crystal
X-ray
diffraction
analysis.
DFT
calculations
performed
two
model
confirmed
that
initial
electrochemical
oxidation
occurs
at
iron
despite
conjugated
nature
highest
occupied
molecular
orbital
is
localized
predominantly
(η5-C5Me5)M
moiety.
An
analysis
bonding
intrinsic
bond
orbitals
quantum
theory
atoms
molecules
suggested
more
covalent
M–X
(X
Cl
N)
bonds
iridium
complex
than
its
rhodium
congener.
Notably,
opposite
trend
was
noted
M–C
bonds,
which
appear
ionic
Ir
complex.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 11, 2025
The
synthesis
of
enantiopure
and
structurally
unique
spiro-type
molecules
is
utmost
significance
in
catalysis,
synthetic
chemistry,
related
fields.
We
present
here
a
general
solution,
nickel-catalyzed
[2
+
2
2]
cycloaddition,
for
accessing
enantioenriched
spiropyridines
from
readily
available
nitriles
alkynes
single
step,
including
(1)
enantio-relay
double
cycloaddition
malononitriles
with
(2)
kinetic
resolution
racemic
pyridine-containing
alkynes.
Both
strategies
feature
broad
substrate
scope
exclusive
regioselectivities,
are
scalable
to
multigram.
Remarkably,
the
integrates
enantio-induction
by
desymmetrizing
dinitriles
during
initial
catalytic
cycle
additional
enantio-enhancement
second
(enantio-relay),
yielding
excellent
enantioselectivities
(>99%
ee
all
examined
examples).
Furthermore,
highly
efficient
strategy
enables
achievement
exceptionally
high
without
compromising
yields
(s
>
200
most
examples),
overcoming
challenges
toward
yield
enantioselectivity.
ability
construct
previously
inaccessible
spiro
structures
lays
groundwork
advancing
spiropyridine
derivatives,
especially
multinitrogen-containing
compounds
as
potential
ligands.
Due
perpendicular
molecular
orientation
inherent
rigidity
architectures
obtained,
we
anticipate
significant
promise
presented
approaches
enhancing
efforts
catalysis.
Organic Letters,
Год журнала:
2024,
Номер
26(35), С. 7324 - 7329
Опубликована: Авг. 22, 2024
Transition
metal-catalyzed
[2
+
2
2]
cycloaddition
of
nitriles
and
two
alkynes
is
an
efficient
method
for
assembling
pyridines.
However,
examples
employing
palladium
catalysis
have
rarely
been
disclosed,
the
processes
reactivity
selectivity
remain
unclear.
We
report
here
a
palladium/copper
dual
diynyl-tethered
malononitriles
terminal
to
synthesize
densely
substituted
This
features
good
substrate
scope,
synthetically
useful
yields,
perfect
regioselectivity.
The
derivatization
pyridine
products
demonstrates
potential
application
this
in
synthesizing
heterocycles
as
ligands
photocatalysis.
Preliminary
mechanistic
studies
suggest
that
reaction
undergoes
aza-oxidative
Pd(0)
with
nitrile
alkyne,
followed
by
alkyne
insertion
reductive
elimination.
presence
copper
crucial
its
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
unknown
Опубликована: Ноя. 4, 2023
The
development
of
a
nickel-catalyzed
reductive
alkyne
hydrocyanation
is
described
using
2-methyl-2-phenylmalononitrile
(MPMN),
C-bound
electrophilic
transnitrilation
reagent.
Reproducibility
issues
led
to
the
detection
oxidized
hemiaminal
impurities
within
N,N-dimethylacetamide.
These
release
formaldehyde
in
situ,
which
was
ultimately
identified
as
critical
reaction
additive.
A
range
diaryl
and
aryl-alkyl
alkynes
underwent
hydrocyanation.
Mechanistic
experiments
revealed
that
MPMN
undergo
Ni-catalyzed
coupling
two
π-components,
leading
controlled
glycolonitrile
active
cyanating
agent.
Organic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(11), С. 3257 - 3262
Опубликована: Янв. 1, 2024
This
work
has
realized
a
facile
assembly
of
succinimide-fused
1,3-cyclohexadienes
via
Co-catalyzed
[2
+
2
2]
cycloaddition
1,6-diynes
to
maleimides.
Furthermore,
the
oxidation
was
carried
out
under
I
/MeONa.
The Journal of Organic Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 13, 2025
A
series
of
polyaryl-substituted
fluoranthenes
is
built
in
good
to
excellent
yields
via
Earth-abundant
metal-catalyzed
[2
+
2+
2]
cycloaddition
1,6-diynes
with
alkynes
developed.
This
method
runs
smoothly
using
a
cheap
catalytic
system
(CoI2/dppe/Zn)
as
the
catalyst.
Generally,
this
strategy
exhibits
low
cost,
high
efficiency,
atom
economy,
and
functional
group
tolerance.
Additionally,
both
terminal
alkynes,
especially
heteroaryl-substituted
acetylenes,
internal
alkyne,
tolerate
work.
Furthermore,
photophysical
properties
selected
also
investigated.
Transition-metal-catalyzed
[2
+
2
2]
cycloaddition
reactions
of
alkynes,
nitriles,
and
other
π
partners
have
been
recognized
as
economic
strategies
to
assemble
aza-six-membered
rings,
but
access
pyrimidin-2-ones
is
not
disclosed.
Herein,
we
report
a
palladium-catalyzed
1,3-diyne-substituted
malononitriles
isocyanates
for
the
construction
polysubstituted
pyrimidin-2-ones.
This
reaction
features
broad
substrate
scope
moderate
high
yields.
Conjugated
pyrimidin-2-one
acting
fluorophore
showcased
potential
fluorescent
chemosensor
Fe(III)
detection.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(19), С. 10463 - 10469
Опубликована: Май 2, 2023
γ-Lactams
are
valuable
heterocycles
in
synthetic
chemistry
and
drug
development.
Here,
we
report
a
reductive
aza-Pauson-Khand
reaction
(aza-PKR)
of
an
alkyne,
nitrile,
Co2(CO)8.
A
wide
array
bicyclic
α,β-unsaturated
γ-lactams
containing
two
adjacent
stereocenters,
including
all-carbon
quaternary
center,
from
alkyne-tethered
malononitriles
efficiently
accessed
high
diastereoselectivity.
Preliminary
mechanistic
investigations
by
experiments
DFT
calculations
reveal
that
the
undergoes
aza-PKR
process
followed
situ
reduction.
The
reducing
reagent
generated
water
also
provides
practical
tool
for
deuterium
incorporation
into
γ-position
lactams
using
D2O
as
source.
This
study
represents
new
mode
[2
+
2
1]
cycloaddition
enables
direct
use
nitrile
aza-heterocycle
synthesis.
