The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(8), С. 5304 - 5313
Опубликована: Апрель 9, 2024
Most
of
the
known
rearrangement
reactions
donor–acceptor
cyclopropanes
(DACs)
involve
migration
cationic
carbon
atom
to
anionic
or
heteroatoms
in
1,3-
1,4-positions.
In
present
work,
we
observed
that
spiro
DACs
based
on
1,3-indanedione
1-indanone
moiety
undergo
intramolecular
1,2-aroyl
when
treated
with
titanium(IV)
chloride
afford
1,4-naphthoquinones
and
α-naphthols
readily.
The
take
place
through
formation
putative
1,3-dipolar
intermediates,
followed
by
cleavage
aroyl
group
adjacent
ring-expansion
products.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
62(1)
Опубликована: Ноя. 2, 2022
A
novel
class
of
highly
activated
donor-acceptor
cyclopropanes
bearing
only
a
single,
vinylogous
acceptor
is
presented.
These
strained
moieties
readily
undergo
cycloadditions
with
aldehydes,
ketones,
thioketones,
nitriles,
naphth-2-ols
and
various
other
substrates
to
yield
the
corresponding
carbo-
heterocycles.
Diastereocontrol
can
be
achieved
through
choice
catalyst
(Brønsted
or
Lewis
acid).
The
formation
tetrahydrofurans
was
shown
enantiospecific
when
chiral
are
employed.
series
mechanistic
kinetic
experiments
conducted
elucidate
plausible
catalytic
cycle
rationalize
stereochemical
outcome.
The Journal of Organic Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 20, 2025
Lewis
acid-enabled
reactions
of
donor-acceptor
cyclopropanes
(DACs)
with
indoline-2-thiones
are
reported.
The
reaction
exhibits
tunable
annulation
depending
on
the
acid
and
substituent
at
N1
indoline-2-thiones.
With
AlCl3
as
1-isopropylindoline-2-thiones
reactants,
a
direct
ring
opening
DACs,
followed
by
intramolecular
nucleophilic
addition/dehydration
takes
place
leading
to
formation
dihydro-2H-thiepino[2,3-b]indoles
in
moderate
good
yields.
Using
Yb(OTf)3
promoter
1-unsubstituted
(3
+
2)
cycloaddition
DACs
accompanied
sulfur
rearrangement
give
3-indolyl-4,5-dihydrothiophenes
In
addition,
synthetic
transformation
3-indolyl-4,5-dihydrothiophene
sulfone
indole-based
axially
chiral
scaffolds
further
extends
utility
structural
complexity.
Synthesis,
Год журнала:
2023,
Номер
55(23), С. 3875 - 3894
Опубликована: Май 22, 2023
Abstract
This
review
discusses
the
utility
of
donor-acceptor
cyclopropanes
(DACs)
for
construction
heterocycles.
In
addition
to
(3+2),
(3+3),
and
(4+3)
cycloaddition
pathways,
nucleophilic
ring-opening
reactions,
intramolecular
transformations,
cycloisomerizations
in
presence
suitable
catalysts
pave
way
generation
heterocycles
from
DACs.
The
mild
reactions
conditions
employed
variety
starting
materials
that
can
be
used
as
reaction
partners
make
DAC
route
heterocycle
synthesis
attractive.
literature
covered
this
is
period
2018
2023.
1
Introduction
2
Synthesis
Nitrogen
Heterocycles
2.1
By
Annulations
with
Anthranils
Azadienes
2.2
Nucleophilic
Attack
Anilines
Hydrazones
2.3
Reaction
Ureas
Thioureas
2.4
Annulation
Reactions
Using
an
Azomethine
Imine
2.5
Other
2.6
Transformations
3
Oxygen
3.1
Intramolecular
3.2
Intermolecular
4
Sulfur
Selenium
4.1
Thiocarbonyl
Substrates
4.2
Thio-
Selenocyanates
Thiosulfonate
Salts
5
N–S
N–O
6
Conclusions
Organic Letters,
Год журнала:
2024,
Номер
26(8), С. 1672 - 1676
Опубликована: Фев. 15, 2024
The
(3
+
2)
cycloaddition/sulfur
rearrangement
reaction
of
donor–acceptor
cyclopropanes
bearing
a
single
keto
acceptor
with
indoline-2-thiones
has
been
realized.
Under
the
catalysis
Sn(OTf)2,
series
functionalized
3-indolyl-4,5-dihydrothiophenes
were
synthesized
moderate
to
excellent
yields.
Organic Letters,
Год журнала:
2023,
Номер
25(16), С. 2857 - 2862
Опубликована: Апрель 14, 2023
Here,
we
report
a
facile
and
efficient
method
for
the
difluoroalkylation
of
vinyl
cyclopropanes
(VCPs)
using
visible-light
organophotoredox
catalysis.
This
strategy
exploits
interplay
α-amino
alkyl
radical-mediated
halogen-atom
transfer
(XAT)
reaction.
The
broad
substrate
scope,
excellent
functional
group
compatibility,
operational
simplicity,
inexpensive
CF2
precursors,
high
efficiency
make
this
protocol
promising
cost-efficient
synthesis
allylic
difluoroalkylated
derivatives.
ACS Catalysis,
Год журнала:
2023,
Номер
13(9), С. 6261 - 6267
Опубликована: Апрель 21, 2023
An
efficient
method
for
a
highly
regio-
and
enantioselective
allylic
substitution
of
vinylcyclopropanes
using
carboxylic
acids
as
oxygen
nucleophile
via
iridium
catalysis
has
been
developed.
This
represents
atom-economic
approach
the
synthesis
synthetically
useful
chiral
building
blocks
in
high
yields.
The
practical
utility
this
is
demonstrated
by
application
products
transformations.
Advanced Synthesis & Catalysis,
Год журнала:
2024,
Номер
366(12), С. 2784 - 2790
Опубликована: Апрель 23, 2024
Abstract
Ytterbium
triflate
catalysed
domino
reaction
of
(3‐formyl‐4‐indolyl)‐derived
donor‐acceptor
cyclopropane
with
primary
amines
provides
a
simple
approach
to
an
unprecedented
tetracyclic
skeleton
in
which
tropane
system
is
peri
‐annulated
indole
core.
This
process
involves
the
formation
imine
and
its
(3+2)‐cross‐cycloaddition
moiety,
yielding
tropane‐fused
core
under
mild
conditions.
These
products
are
significant
interest
for
pharmacology
as
potential
hybrid
molecules
dual
mode
action.
Organic Letters,
Год журнала:
2024,
Номер
26(25), С. 5341 - 5346
Опубликована: Июнь 14, 2024
An
unprecedented
VCP-CP
(vinylcyclopropane-cyclopentene)
rearrangement
approach
has
been
established
herein
by
virtue
of
the
pyridine-boronyl
radical
catalyzed
intramolecular
ring
expansions.
This
metal-free
pathway
harnesses
readily
available
catalysts
and
unactivated
vinylcyclopropane
starting
materials,
providing
an
array
cyclopentene
derivatives
chemoselectively
under
relatively
mild
conditions.
Mechanistic
studies
support
idea
that
boronyl
engages
in
generation
allylic/ketyl
species,
thus
inducing
opening
cyclopropanes
following
cyclization
processes.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 15, 2024
Abstract
The
substituted
tetrahydrofuran
core
is
a
structural
motif
in
many
biologically
active
and
natural
compounds.
However,
the
scarcity
of
enantioselective
methods
developed
towards
its
synthesis
makes
this
field
challenging
attractive
to
explore.
Herein,
first
Brønsted‐base
catalyzed
(3+2)
annulation
donor‐acceptor
cyclopropanes
with
aldehydes
ketones
affording
enantioenriched
2,3,5‐substituted
tetrahydrofurans
reported.
reaction
concept
based
on
activation
racemic
β‐cyclopropyl
by
chiral
bifunctional
Brønsted
base
which
catalyzes
for
range
ketones.
For
aldehydes,
furnished
excellent
yield,
good
diastereoselectivity
enantioselectivity
up
>99
%
ee
.
Surprisingly,
aromatic
afforded
cis
‐2,5‐substituted
as
major
diastereoisomer,
while
aliphatic
trans
‐cycloadduct
was
favored.
also
proceeds
well
spiro
yields
enantioselectivities
(up
99
).
Hammett
studies
have
been
conducted
elucidate
influence
electronic
nature
benzaldehydes
stereoselectivity.
Based
diastereochemical
outcome
two
paths
are
proposed.
Finally,
diastereoselective
synthetic
transformations
demonstrate
potential
obtained
products.
