Catalysts,
Год журнала:
2022,
Номер
12(8), С. 915 - 915
Опубликована: Авг. 19, 2022
α-Imino
gold
carbenoid
species
have
been
recognized
as
key
intermediates
in
a
plethora
of
processes
involving
gold-activated
alkynes.
Here,
we
explored
the
pathways
Au(I)-catalyzed
[3
+
2]
reaction
between
mild
nucleophiles:
anthranil,
1,2,4-oxadiazole,
or
4,5-dihydro-1,2,4-oxadiazole,
and
an
ynamide,
PhC≡C-N(Ts)Me,
proceeding
via
formation
aforementioned
α-imino
carbene
intermediate
which,
after
intramolecular
capture,
regioselectively
produces
2-amino-3-phenyl-7-acyl
indoles,
N-acyl-5-aminoimidazoles,
N-alkyl-4-aminoimidazoles,
respectively.
In
all
cases,
regioselectivity
substituents
at
2,
3
7-acyl-indole
ring
4,
5
substituted
imidazole
is
decided
first
transition
state,
attack
nitrogen
on
C1
C2
carbon
activated
ynamide.
A
subsequent
steep
energy
drop
furnishes
carbene.
These
features
are
more
pronounced
for
anthranil
4,5-dihydro-1,2,4-oxadiazole
reactions.
Strikingly,
significant
due
to
unstable
carbene,
which
spontaneous
benzaldehyde
elimination
converted
stabilized
one.
Compared
1,2,4-oxadiazoles
4,5-dihydro-1,2,4-oxadiazoles
found
be
significantly
complex
than
anticipated
original
research.
For
instance,
compared
five-member
from
one
competitive
route
involves
consisting
four-member
condensed
with
three-member
ring,
metathesis
expansion
led
ring.
Chinese Journal of Chemistry,
Год журнала:
2023,
Номер
41(23), С. 3299 - 3304
Опубликована: Авг. 3, 2023
Comprehensive
Summary
An
unprecedented
copper
nitrate‐mediated
bond
cleavage
of
alkynes
was
developed
for
the
modular
synthesis
isoxazoles,
where
either
C—S
or
C≡C
triple
cleaved
selectively.
Substituents
attached
to
bonds
could
differentiate
chemical
and
reaction
pathways
disparately.
Various
transformations
products
illustrate
promising
applications
given
protocols.
Cell Reports Physical Science,
Год журнала:
2023,
Номер
4(11), С. 101645 - 101645
Опубликована: Окт. 30, 2023
Isoxazoles
and
their
derivatives
have
been
verified
to
be
versatile
building
blocks
crucial
intermediates
for
the
synthesis
of
a
range
useful
N-containing
molecules,
especially
valuable
N-heterocycles.
However,
catalytic
asymmetric
reaction
isoxazole
has
rarely
explored,
there
is
no
systematic
summary
date.
In
this
perspective,
we
summarize
recent
advances
in
isoxazoles
benzisoxazoles
according
different
types
reactions:
(1)
transition-metal-catalyzed
ring
contraction
isoxazoles,
(2)
copper-catalyzed
hydroamination
alkenes
alkynes
with
benzisoxazoles,
(3)
formal
annulations
benzisoxazoles.
Finally,
propose
remaining
challenges
opportunities
future
breakthroughs
area.
Organic Chemistry Frontiers,
Год журнала:
2023,
Номер
11(1), С. 67 - 73
Опубликована: Ноя. 7, 2023
A
unique
and
efficient
copper
catalytic
system
has
been
established
for
the
synthesis
of
fluorinated
2-azadienes
from
isoxazoles
CF
3
-
N
-tosylhydrazones
via
crosscoupling
reactions
vinyl
nitrenes
with
fluoroalkyl
carbenes.
Organic Letters,
Год журнала:
2024,
Номер
26(9), С. 1753 - 1757
Опубликована: Фев. 27, 2024
In
this
study,
we
discover
a
good
NO/HNO
precursor,
N-hydroxypyridinesulfonamide,
and
the
regioselective
radical
nitrososulfonylation
reaction
of
propargyl
alcohols.
Direct
unique
isoxazole
synthesis
afforded
good-to-high
yield
5-alkyl-3-aryl-4-pyridinesulfonylisoxazoles.
Copper-catalyzed
aerobic
oxidation
could
efficiently
proceed
in
presence
thiazolidine-2,4-dione.
This
work
provides
powerful
method
for
functionalization
alkyl-substituted
isoxazoles
explores
new
investigation
route
drug–drug
discovery.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(17), С. 12378 - 12386
Опубликована: Авг. 22, 2024
Photocatalyst-free
visible
light-enabled
direct
oxygenation
of
furan-tethered
α-azidoketones
was
studied.
The
reaction
yielded
various
products
depending
on
the
substituents,
with
isoxazoles
forming
as
major
products.
findings
suggest
that
singlet
oxygen
generated
during
and
reacted
in
a
[4
+
2]
fashion
to
yield
endoperoxides,
which
rearranged
multiple
ways
generate
isoxazoles.
Some
synthesized
were
evaluated
α-glucosidase
inhibitors,
three
them
5bi,
5bj,
5bl
exhibited
good
activity
IC50
values
454.57
±
29.34,
147.84
2.28,
272.58
42.06
μM,
respectively,
when
compared
standard
drug
acarbose
(IC50
=
1224.33
126.72
μM).
Abstract
A
simple
two‐step
protocol
for
the
synthesis
of
3‐aryl/hetaryl‐4‐nitro‐5‐styrylisoxazole
was
elaborated.
large
series
novel
5‐styrylisoxazoles
(36
compounds)
containing
various
substituents
at
positions
3
and
5
isoxazole
cycle
obtained.
The
title
compounds
revealed
fluorescent
properties
in
visible
region,
possessing
emission
maximum
up
to
610nm.
effect
solvatochromism
chemosensor
towards
a
number
metal
cations
were
demonstrated.
Cytotoxic
activity
against
MCF‐7
(breast
carcinoma),
HCT‐116
(colon
A549
(pulmonary
carcinoma)
WI38
(fibroblasts
from
lung
tissue)
cell
lines
tested
toxicity
concentration
range
10–100
μM
found
several
compounds.
Chemical Communications,
Год журнала:
2023,
Номер
59(70), С. 10536 - 10539
Опубликована: Янв. 1, 2023
A
Ru(II)
catalyzed
regioselective
Heck-type
C-H
olefination
of
isoxazole
with
unactivated
allyl
phenyl
sulfone
is
revealed.
The
solvent
DCM
offers
dual
sp2-sp2
activation
via
an
N-directed
strategy,
leading
to
ortho-olefinated
isoxazoles
exclusive
E-selectivity.
On
the
other
hand,
in
DCE
solvent,
serves
as
nitrile
synthon
and
leads
o-olefinated
benzonitrile.
At
a
higher
temperature
(110
°C)
DCE,
after
ortho-olefination
mediated
cleavage
delivered
functionality.
Organic & Biomolecular Chemistry,
Год журнала:
2022,
Номер
20(48), С. 9742 - 9745
Опубликована: Янв. 1, 2022
The
direct
conversion
of
aryl
boronic
acids
and
anthranils
to
acridines
has
been
realized
herein,
via
the
catalysis
copper
species
under
acidic
conditions.
Synthesis,
Год журнала:
2023,
Номер
56(02), С. 281 - 292
Опубликована: Окт. 17, 2023
Abstract
A
readily
prepared
and
versatile
heterogeneous
catalyst
composed
of
copper
nanoparticles
supported
on
montmorillonite
K-10
(CuNPs/MK-10)
has
proven
to
be
highly
effective
in
catalyzing
the
synthesis
isoxazoles
through
various
one-pot
methodologies
with
high
atom
economy.
These
allow
for
use
available
starting
materials,
including
aldehydes
alkynes
1,3-dipolar
cycloaddition
reactions,
as
well
via
cycloisomerization
ynones.
Additionally,
CuNPs/MK-10
promoted
situ
formation
ynones
an
acyl
Sonogashira
coupling.
Furthermore,
a
three-step
methodology
was
also
developed,
from
carboxylic
acids
involving
generation
chlorides.
