The Journal of Organic Chemistry,
Год журнала:
2020,
Номер
85(23), С. 15752 - 15759
Опубликована: Ноя. 13, 2020
Rhodium-catalyzed
directed
C-H
functionalization
of
2-arylindazoles
with
N-sulfonylformaldimines
has
been
developed
to
provide
a
variety
N-benzylarylsulfonamide
derivatives
good
excellent
yields.
Different
activated
aldehydes
like
ethyl
glyoxalate
and
2,2,2-trifluoroacetaldehyde
also
efficiently
underwent
nucleophilic
addition
2-arylindazoles.
These
selective
transformations
occur
through
the
control
C3
nucleophilicity
indazole
moiety.
Mechanistic
studies
suggest
that
activation
step
may
be
rate-limiting
step.
Advanced Synthesis & Catalysis,
Год журнала:
2021,
Номер
363(22), С. 5047 - 5071
Опубликована: Окт. 1, 2021
Abstract
Electrochemical
synthesis
offers
a
mild,
simple,
and
efficient
tool
for
the
preparation
of
interesting
useful
molecules,
thus
eluding
severe
chemical
oxidizing
reducing
agents
used
in
conventional
synthetic
methods.
In
particular,
electrochemical
C−H
activation
is
expected
to
play
an
important
role
direct
functionalization
heterocyclic
compounds.
Over
past
few
decades,
research
interest
imidazopyridine
indazole
has
increased
significantly
due
their
multipurpose
uses
medicinal
industrial
chemistry.
Therefore,
structural
modification
these
heterocycles
using
electro‐oxidation
become
one
topics
among
organic
chemistry
recent
time.
This
review
provides
comprehensive
discussion
indazoles
imidazopyridines
published
so
far.
A
summary
current
challenges
future
direction
development
green
methods
also
presented.
magnified
image
Chemical Communications,
Год журнала:
2022,
Номер
58(28), С. 4435 - 4455
Опубликована: Янв. 1, 2022
Indazole
and
pyrazole
are
renowned
as
a
prodigious
class
of
heterocycles
having
versatile
uses
in
medicinal
well
industrial
chemistry.
Considering
sustainable
approaches,
recently,
photocatalysis
has
become
an
indispensable
tool
organic
chemistry
due
to
its
application
for
the
activation
small
molecules
use
clean
energy
source.
In
this
review,
we
have
highlighted
metal-based
photocatalysts,
photoredox
catalysts,
transfer
photocatalysts
electron-donor-acceptor
complexes
functionalization
indazole
pyrazole.
This
perspective
is
arranged
based
on
types
reactions
A
detailed
discussion
regarding
reaction
mechanism
each
given
provide
comprehensive
guide
reader.
Finally,
summary
existing
challenges
future
outlook
towards
development
efficient
photocatalytic
methods
these
also
presented.
Green Chemistry,
Год журнала:
2022,
Номер
24(8), С. 3056 - 3080
Опубликована: Янв. 1, 2022
This
critical
review
chronologically
summarizes
the
metal-free
coupling
methodologies
of
C(sp
3
)–H
sources
with
heteroarenes
induced
by
visible
light.
The
articles
which
are
published
up
to
January
2022
on
this
topic
enclosed
here.
Organic Chemistry Frontiers,
Год журнала:
2022,
Номер
9(5), С. 1445 - 1450
Опубликована: Янв. 1, 2022
A
visible-light-driven
rhodamine
B-catalyzed
transition-metal-free
3-ethoxycarbonylmethylation
of
2-aryl-2
H
-indazoles
and
imidazo[1,2-
a
]pyridines
(40
examples)
using
commercially
available
α-bromoesters
was
realized
in
water.
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(8), С. 1591 - 1628
Опубликована: Янв. 1, 2023
Photoredox
catalysis
has
demonstrated
rapid
evolution
in
the
field
of
synthetic
organic
chemistry.
On
other
hand,
splendour
cascade
reactions
providing
complex
molecular
architectures
renders
them
a
cutting-edge
research
area.
Therefore,
merging
photocatalysis
with
synthesis
brings
out
paradigm
immense
potential.
The
development
photocascade
for
target
molecule
particular
skeleton
and
stereochemical
framework
presents
certain
challenges
but
provides
robust
environmentally
benign
alternative.
This
comprehensive
review
assembles
all
accomplishments
highlights
visible-light-induced
literature
coverage
up
to
October
2022.
Organic Letters,
Год журнала:
2023,
Номер
25(24), С. 4422 - 4428
Опубликована: Июнь 8, 2023
Presented
herein
is
a
condition-controlled
selective
synthesis
of
pyranone-tethered
indazoles
or
carbazole
derivatives
via
the
cascade
reactions
N-nitrosoanilines
with
iodonium
ylides.
Mechanistically,
formation
former
involves
an
unprecedented
process
including
nitroso
group-directed
C(sp2)–H
bond
alkylation
N-nitrosoaniline
ylide
followed
by
intramolecular
C-nucleophilic
addition
to
moiety,
solvent-assisted
cyclohexanedione
ring
opening,
and
transesterification/annulation.
On
contrary,
latter
initial
annulation
denitrosation.
These
developed
protocols
feature
easily
controllable
selectivity,
mild
reaction
conditions,
clean
sustainable
oxidant
(air),
valuable
products
that
are
structurally
diverse.
In
addition,
utility
was
showcased
their
facile
diverse
transformations
into
synthetically
biologically
interesting
compounds.
ACS Catalysis,
Год журнала:
2024,
Номер
14(2), С. 1193 - 1204
Опубликована: Янв. 9, 2024
Herein,
the
C3–H
alkylation
of
2H-indazoles
and
indoles
with
sulfoxonium
ylides
is
developed
under
visible-light
photocatalysis.
This
protocol
employs
easily
accessible
reagents,
a
wide
range
2H-indazoles,
indoles,
are
suitable
for
this
reaction
to
afford
desired
products
benign
conditions.
Synergistic
experimental
computational
studies
suggest
that
involving
photocatalysis
could
proceed
via
different
mechanistic
pathways.
For
C3-alkylation
triplet
energy
transfer
pathway
proposed
quenching
excited
photocatalyst.
Subsequently,
formed
state
undergo
radical
attack
on
C═S
moiety
ylides.
After
dissociation
DMSO
1,2-H
migration,
final
product
be
yielded.
However,
such
not
applicable
indoles.
Instead,
converted
C-centered
in
presence
KH2PO4
photoredox
The
can
C3-site
thus
lead
Organic Chemistry Frontiers,
Год журнала:
2021,
Номер
8(13), С. 3286 - 3291
Опубликована: Янв. 1, 2021
A
general
transition-metal-free
photocatalytic
decarboxylative
3-alkylation
reaction
of
2-aryl-2H-indazoles
was
developed
under
visible-light
irradiation
mild
conditions.