ChemSusChem,
Journal Year:
2022,
Volume and Issue:
15(15)
Published: May 4, 2022
N-heteroarenes
represents
one
of
the
most
important
chemicals
in
pharmaceuticals
and
other
bio-active
molecules,
which
can
be
easily
accessed
from
oxidation
N-heterocycles
over
metal
catalysts.
Herein,
metal-free
oxidative
dehydrogenation
into
was
developed
using
molecular
oxygen
as
terminal
oxidant.
The
nitrogen-doped
carbon
materials
were
facilely
prepared
via
simple
pyrolysis
process
biomass
(carboxymethyl
cellulose
sodium)
dicyandiamide
nitrogen
source,
respectively,
they
discovered
to
robust
for
under
mild
conditions
(80
°C
1
bar
O2
)
with
water
green
solvent.
Diverse
including
1,2,3,4-tetrahydroisoquinolines,
indolines
1,2,3,4-tetrahydroquinoxalines
smoothly
converted
high
excellent
yields
(76->99
%).
Superoxide
radical
(⋅O2
-
hydroxyl
(⋅OH)
probed
reactive
species
N-heteroarenes.
More
importantly,
catalyst
reused
a
stability.
method
provides
an
environmentally
friendly
economical
route
access
N-hetero-aromatic
commodities.
Organic Chemistry Frontiers,
Journal Year:
2021,
Volume and Issue:
8(11), P. 2820 - 2862
Published: Jan. 1, 2021
Quinoxalines
are
observed
in
several
bioactive
molecules
and
have
been
widely
employed
designing
for
DSSC's,
optoelectronics,
sensing
applications.
Therefore,
developing
newer
synthetic
routes
as
well
novel
ways
their
functionalization
is
apparent.
Green Chemistry,
Journal Year:
2021,
Volume and Issue:
23(12), P. 4446 - 4450
Published: Jan. 1, 2021
A
visible-light-induced
aerobic
dehydrogenation
reaction
of
N-heterocycles
has
been
achieved
via
the
catalysis
an
organoboron
compound,
under
metal-free
conditions.
Advanced Synthesis & Catalysis,
Journal Year:
2021,
Volume and Issue:
363(5), P. 1390 - 1400
Published: Jan. 21, 2021
Abstract
A
visible
light‐rose
bengal‐TBHP
mediated,
controlled
oxidation
of
N
‐substituted
1,2,3,4‐tetrahydroisoquinolines
is
developed
for
the
synthesis
3,4‐dihydroisoquinolin‐1(2
H
)‐ones
and
isoquinolin‐1(2
)‐ones.
The
present
method
feature's
a
broad
substrate
scope,
good
functional
group
tolerances,
products
were
prepared
in
to
excellent
yields.
methodology
further
demonstrated
isoindolo[2,1‐b]
isoquinolin‐5(7
)‐one
(topoisomerase‐I
inhibitor).
magnified
image
Organic Letters,
Journal Year:
2022,
Volume and Issue:
24(9), P. 1786 - 1790
Published: Feb. 25, 2022
Herein
is
introduced
the
application
of
"super-electron-donor"(SED)
2-azaallyl
anions
in
a
tandem
reduction/radical
cyclization/radical
coupling/aromatization
protocol
that
enables
rapid
construction
isoquinolines.
The
value
this
transition-metal-free
method
highlighted
by
wide
range
isoquinoline
ethyl
amines
prepared
with
good
functional
group
tolerance
and
yields.
An
operationally
simple
gram
scale
synthesis
also
conducted,
confirming
scalability.
Inorganic Chemistry,
Journal Year:
2022,
Volume and Issue:
61(16), P. 6193 - 6208
Published: April 8, 2022
Photoredox
catalysis
constitutes
a
very
powerful
tool
in
organic
synthesis,
due
to
its
versatility,
efficiency,
and
the
mild
conditions
required
by
photoinduced
transformations.
In
this
paper,
we
present
an
efficient
selective
photocatalytic
procedure
for
aerobic
oxidative
dehydrogenation
of
partially
saturated
N-heterocycles
afford
respective
N-heteroarenes
(indoles,
quinolines,
acridines,
quinoxalines).
The
protocol
involves
use
new
Ir(III)
biscyclometalated
photocatalysts
general
formula
[Ir(C^N)2(N^N')]Cl,
where
C^N
ligand
is
2-(2,4-difluorophenyl)pyridinate,
N^N'
are
different
ligands
based
on
2-(2'-pyridyl)benzimidazole
scaffold.
In-depth
electrochemical
photophysical
studies
as
well
DFT
calculations
have
allowed
us
establish
structure-activity
relationships,
which
provide
insights
rational
design
metal-based
dyes
oxidation
reactions.
addition,
formulated
dual
mechanism,
mediated
radical
anion
superoxide,
above-mentioned
The Journal of Organic Chemistry,
Journal Year:
2024,
Volume and Issue:
89(7), P. 4530 - 4537
Published: March 14, 2024
A
copper-catalyzed
method
for
the
dehydrogenation
of
various
nitrogen-containing
heterocycles
to
furnish
quinolines
and
indoles
has
been
developed.
range
1,2,3,4-tetrahydroquinolines
underwent
by
employing
2
mol
%
copper
complex
Cat
3
as
a
catalyst
using
O2
an
oxidant
at
120
°C
in
1,2-dichlorobenzene
afford
desired
quinolines.
The
enables
variety
indolines
presence
2,
10
TEMPO
additive
under
room
temperature
tetrahydrofuran
high
yields.
Mechanistic
studies
suggested
that
dehydrogenative
activity
is
ascribed
formation
copper(II)
active
species
from
copper(I)
complexes
oxidized
O2,
which
was
proved
high-resolution
mass
spectrometry
(HRMS).
reaction
proceeds
via
superoxide
radical
anion
(·O2–)
electron
paramagnetic
resonance
(EPR)
spectrometry.
In
situ
infrared
spectroscopy
revealed
dihydroquinoline
intermediate
formed
1,2,3,4-tetrahydroquinolines.
