Chemical Reviews,
Journal Year:
2023,
Volume and Issue:
123(16), P. 10302 - 10380
Published: Aug. 14, 2023
Nitroxides,
also
known
as
nitroxyl
radicals,
are
long-lived
or
stable
radicals
with
the
general
structure
R1R2N–O•.
The
spin
distribution
over
nitroxide
N
and
O
atoms
contributes
to
thermodynamic
stability
of
these
radicals.
presence
bulky
N-substituents
R1
R2
prevents
radical
dimerization,
ensuring
their
kinetic
stability.
Despite
reactivity
toward
various
transient
C
some
nitroxides
can
be
easily
stored
under
air
at
room
temperature.
Furthermore,
oxidized
oxoammonium
salts
(R1R2N═O+)
reduced
anions
(R1R2N–O–),
enabling
them
act
valuable
oxidants
reductants
depending
on
oxidation
state.
Therefore,
they
exhibit
interesting
across
all
three
states.
Due
fascinating
properties,
find
extensive
applications
in
diverse
fields
such
biochemistry,
medicinal
chemistry,
materials
science,
organic
synthesis.
This
review
focuses
versatile
For
use
other
important
fields,
we
will
refer
several
articles.
introductory
part
provides
a
brief
overview
history
chemistry.
Subsequently,
key
methods
for
preparing
discussed,
followed
by
an
examination
structural
diversity
physical
properties.
main
portion
this
is
dedicated
reactions,
wherein
parent
corresponding
serve
active
species.
It
demonstrated
that
functional
groups
(such
alcohols,
amines,
enolates,
alkanes
among
others)
efficiently
oxidized.
These
oxidations
carried
out
using
catalysts
combination
stoichiometric
terminal
oxidants.
By
reducing
anions,
become
effective
reagents
intriguing
Nitroxides
possess
ability
selectively
react
making
useful
terminating
cascade
reactions
forming
alkoxyamines.
Depending
structure,
alkoxyamines
weak
C–O
bonds,
allowing
thermal
generation
through
reversible
bond
cleavage.
Such
thermally
generated
participate
transformations,
discussed
end
review.
application
strategy
natural
product
synthesis
presented.
Organic Chemistry Frontiers,
Journal Year:
2023,
Volume and Issue:
10(15), P. 3929 - 3950
Published: Jan. 1, 2023
This
review
will
focus
on
the
electrochemical
synthesis
of
diversified
functionalized
oxindole
derivatives
through
C-S,
C-O,
C-C,
C-Se,
and
C-N
bond
formation
over
past
decade.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(9), P. 1792 - 1796
Published: Feb. 28, 2024
A
mild
and
effective
strategy
for
the
asymmetric
synthesis
of
C2-quaternary
indolin-3-ones
from
2-alkynyl
arylazides
ketones
by
gold/chiral
amine
relay
catalysis
is
described.
In
this
reaction,
undergo
gold-catalyzed
cyclization,
nucleophilic
attack,
oxidation
to
form
intermediate
2-phenyl-3H-indol-3-ones,
followed
an
l-proline-catalyzed
Mannich
reaction
with
ketones,
afford
corresponding
products
in
satisfactory
yields
excellent
enantio-
diastereoselectivities.
Green Chemistry,
Journal Year:
2023,
Volume and Issue:
25(24), P. 10144 - 10181
Published: Jan. 1, 2023
The
electrochemical
cascade
process
majorly
satisfies
the
essential
criteria
of
green
synthesis.
Being
an
Integrated
synthetic
strategy
it
can
produce
more
molecules
in
a
shorter
time
and
thus
provides
modern
strategic
tool
arsenal
chemists.
Organic Letters,
Journal Year:
2023,
Volume and Issue:
26(1), P. 68 - 72
Published: Dec. 31, 2023
A
metal-free
oxidative
intramolecular
dearomative
spirocyclization
of
indole-3-formyl-2-carboxamides
has
been
developed
for
the
first
time,
affording
spiropseudoindoxyls
in
good
yields.
This
domino
process
proceeds
through
sequential
oxidation,
decarboxylation
and
ipso-arylation.
The
unique
feature
this
approach
includes
compatibility
N-protected-indole-2-carboxamides.
Further,
a
hitherto
unknown
rearrangement
to
indoloquinolones
achieved.
synthetic
utility
strategy
also
showcased
by
construction
natural
alkaloid,
isocryptolepine.
2,2-Disubstituted
indolin-3-ones,
which
are
essential
components
in
many
manufactured
chemicals,
dyes,
and
naturally
occurring
bioactive
alkaloids,
have
emerged
as
exciting
synthetic
targets.
Much
attention
has
been
paid
to
accessing
these
units,
particularly
an
asymmetric
fashion,
during
the
last
decade.
In
this
review
article,
we
discuss
current
state
of
available
methods
with
existing
mechanistic
pathways
for
chiral
indolin-3-one
derivatives
under
various
catalytic
systems.
This
overall
presentation
protocols
access
2,2-disubstituted
or
fused
indolin-3-ones
aza-quaternary
centre
is
categorized
based
on
reaction
modes
2-substituted-3H-indole-3-one
other
similar
protocols.
Synlett,
Journal Year:
2023,
Volume and Issue:
34(13), P. 1539 - 1548
Published: Jan. 26, 2023
Abstract
2,2-Disubstituted
indoxyls
are
commonly
found
within
natural
products
and
bioactive
molecules.
Among
the
numerous
methods
to
access
such
motifs,
dearomative
transformation
of
indoles
represents
an
attractive
approach.
Despite
much
development,
a
potential
gap
exists
in
oxidative
union
readily
accessible
2-substituted
with
nucleophilic
partners,
where
general
accommodating
2-alkyl
substitution
broad
range
nucleophiles
is
lacking.
Herein,
we
describe
development
user-friendly
solution
this
challenge
highlight
its
utility
synthesis
complex
alkaloids.
1
Introduction
2
Synthesis
Indoxyls
via
Dearomatization
Indoles:
Background
3
Oxidative
2-Alkylindoles
Indoxyls:
Development
4
Selected
Scope
Preliminary
Investigations
toward
Asymmetric
Coupling
5
Application
Total
Complex
Alkaloids
6
Conclusions
