Organic Letters,
Journal Year:
2022,
Volume and Issue:
24(3), P. 826 - 831
Published: Jan. 14, 2022
We
disclose
a
Ag-catalyzed
asymmetric
interrupted
Barton–Zard
reaction
of
α-aryl-substituted
isocyanoacetates
with
2-
and
3-nitroindoles,
which
enables
the
dearomatization
nitroindoles
hence
offers
rapid
access
to
an
array
optically
active
tetrahydropyrrolo[3,4-b]indole
derivatives
bearing
three
contiguous
stereogenic
centers,
including
two
tetrasubstituted
chiral
carbon
atoms
pretty
outcomes
(up
99%
yield,
91:9
dr,
96%
ee).
The
synthetic
potential
protocol
was
showcased
by
gram-scale
versatile
transformations
product.
Asian Journal of Organic Chemistry,
Journal Year:
2022,
Volume and Issue:
11(5)
Published: March 7, 2022
Abstract
The
2,3‐dihydrobenzofuran
heterocyclic
systems
are
found
in
various
biologically
active
natural
and
pharmaceutical
products
of
biological
relevance
such
as
Phalarine,
Rocaglamide,
Furaquinocin
A.
interest
the
study
2,3‐dihydrobenzofurans
is
constantly
increasing
because
their
numerous
properties
anti‐tumor,
anti‐cancer,
anti‐tubercular,
anti‐malarial
activities.
Different
methods
have
been
established
towards
synthesis
involved
via
intra‐
inter‐molecular
reactions.
Besides,
1,3‐dihydroisobenzofuran
structure
has
identified
a
fundamental
nucleus
many
products,
bioactive
compounds,
functional
molecules
(e.
g.,
Pestacin,
Isopestacin,
Citalopram,
Xylarinol
B,
Matriisobenzofuran,
Thunberginol
F7‐O‐
β
‐D‐glucopyranoside).
On
other
hand,
1,3‐disubstituted
isobenzofurans
powerful
structural
motifs
with
wide
range
activities,
like
anti‐inflammatory,
anti‐histaminic,
anti‐HIV.
In
last
few
years,
decent
number
diligent
synthetic
approaches
demonstrated
toward
synthesizing
isobenzofurans.
This
review
focuses
on
effective
routes
developed
to
construct
1,3‐dihydroisobenzofurans
applications
recent
years.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(15), P. 3310 - 3315
Published: April 8, 2024
A
catalyst
system
consisting
of
a
chiral
phosphoramidite
ligand
and
Pd2(dba)3·CHCl3
causes
the
decarboxylation
5-vinyloxazolidine-2,4-diones
to
generate
amide-containing
aza-π-allylpalladium
1,3-dipole
intermediates,
which
are
capable
triggering
dearomatization
3-nitroindoles
for
diastereo-
enantioselective
[3+2]
cycloaddition,
leading
formation
series
highly
functionalized
pyrroloindolines
containing
three
contiguous
stereogenic
centers
with
excellent
results
(up
99%
yield,
88:12
dr,
96%
ee).
The Journal of Organic Chemistry,
Journal Year:
2022,
Volume and Issue:
87(9), P. 6025 - 6037
Published: April 18, 2022
A
dearomatization
process
of
3-nitroindoles
enabled
using
palladium-catalyzed
decarboxylative
[4
+
2]
cycloaddition
either
2-alkylidenetrimethylene
carbonates
or
2-(hydroxymethyl)-3-arylallyl
has
been
developed,
affording
a
wide
range
indoline-fused
tetrahydropyrans
in
good
yields
with
excellent
diastereoselectivities.
This
reaction
features
substrate
scope
and
mild
conditions
represents
the
first
example
application
π-allyl
palladium
1,4-[O,C]-dipole
species
for
dearomative
electron-deficient
heteroarenes.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(13), P. 2623 - 2628
Published: March 24, 2024
An
efficient
dearomative
cyclization
of
2-nitrobenzofurans
via
a
thiol-triggered
tandem
Michael
addition/intramolecular
Henry
reaction
has
been
developed.
A
range
thiochromeno[3,2-b]benzofuran-11-ols
and
tetrahydrothieno[3,2-b]benzofuran-3-ols
could
be
obtained
in
up
to
99%
yield
>20:1
dr.
The
valuable
thiochromone
fused
benzofurans
prepared
with
the
2-mercaptobenzaldehyde
reaction/rearomatization/oxidative
dehydrogenation
process
one-pot
two-step
operation.
mechanism
for
was
tentatively
proposed.
Organic Letters,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 15, 2025
Herein,
we
disclose
a
novel
organocatalytic
approach
for
the
enantioselective
synthesis
of
1,4-sulfur-bridged
piperidinone
skeletons
via
sequential
aza-Michael/Michael/Mannich
domino
reaction
2-aminochalcones
and
5-alkenyl-thiazolones.
The
one-pot
catalyzed
by
bifunctional
squaramide
catalyst
furnishes
bridged
polycyclic
compounds
with
five
contiguous
stereocenters
(three
tertiary,
two
heteroquaternary)
in
excellent
yields
(up
to
95%)
stereochemical
outcomes
99%
ee
up
>20:1
dr).
methodology
offers
outstanding
control
on
regio-
chemoselectivity,
showcasing
broad
substrate
compatibility.
Additionally,
is
scalable
postsynthetic
transformation
spirothiazolone-tetrahydroquinoline
derivative
further
amplifies
synthetic
utility
methodology.
European Journal of Organic Chemistry,
Journal Year:
2022,
Volume and Issue:
2022(18)
Published: April 5, 2022
Abstract
Dearomatization
reactions
employing
simple
aromatic
compounds
have
showcased
remarkable
progress
in
the
recent
decade
and
emerged
as
one
of
most
straightforward
powerful
tools
for
creation
highly
functionalized,
three‐dimensional
molecular
frameworks
commonly
encountered
medicinal
chemistry
life
sciences.
Among
use,
nitro(hetero)arenes,
which
feature
a
less
pronounced
character
due
to
presence
electron‐withdrawing
nitro
group,
been
extensively
used
different
types
dearomatization
reactions.
The
dearomative
annulation
reaction
serves
versatile
method
construction
complex
polycyclic
systems.
This
overview
presents
brief
summary
impressive
advances
nitro(hetero)arenes
provides
some
inspirations
future
research.
Organic & Biomolecular Chemistry,
Journal Year:
2022,
Volume and Issue:
20(23), P. 4681 - 4698
Published: Jan. 1, 2022
Salicyloylbenzene/heterocycles
are
privileged
scaffolds
found
in
many
natural
products
and
bioactive
molecules.
Numerous
useful
approaches
for
the
preparation
of
these
have
been
developed
recent
years.
Among
approaches,
chromone-based
reactants
demonstrated
their
importance
synthesis
salicyloylbenzene/heterocycle
with
structural
complexity
potential
biological
appeal.
In
this
review,
advances
salicyloylbenzene/heterocycles
summarized
discussed
according
to
which
could
be
achieved
one
step
via
ring-opening
skeletal
reconstruction
reactions.
Both
mechanisms
applications
corresponding
organic
medicinal
chemistry
also
described.
Chirality,
Journal Year:
2022,
Volume and Issue:
34(7), P. 1019 - 1034
Published: May 6, 2022
Abstract
A
readily
available
chiral
cyclohexanediamine‐derived
bifunctional
tertiary
amine‐squaramide
catalyst
is
more
effective
for
the
asymmetric
dearomative
1,3‐dipolar
cycloaddition
of
2‐nitrobenzofurans
and
N
‐2,2,2‐trifluoroethylisatin
ketimines.
range
structurally
diverse
spiro‐fused
polyheterocyclic
compounds
containing
oxindole,
pyrrolidine,
hydrobenzofuran
motifs
were
smoothly
obtained
in
excellent
results
(up
to
99%
yield,
>20:1
dr
all
cases
up
ee).
This
method
features
high
efficiency,
mild
reaction
conditions,
exquisite
induction,
wide
functional
group
tolerance,
great
potential
scale‐up
synthesis,
attractive
product
diversification.
Organic Chemistry Frontiers,
Journal Year:
2022,
Volume and Issue:
9(12), P. 3322 - 3327
Published: Jan. 1, 2022
The
higher-order
[10
+
2]
cycloaddition
of
3-nitroindoles
and
2-alkylidene-1-indanones
enables
the
dearomatization
affords
a
range
structurally
diverse
cyclopenta[
b
]indolines
with
excellent
results.
