Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(33)
Published: June 13, 2023
A
ligand-controlled
regiodivergence
in
Ni-catalyzed
rearrangement
of
vinylcyclopropanes
to
1,4-
or
1,5-disubstituted
cyclopentenes
is
reported.
The
cyclopentene
selectively
obtained
depending
on
the
choice
ligands.
Detailed
kinetic
studies
and
density
functional
theory
calculations
catalytic
cycle
revealed
that
product
selectivity
determined
at
reductive
elimination
step
from
six-membered
η1
-allyl
intermediate.
Angewandte Chemie International Edition,
Journal Year:
2022,
Volume and Issue:
62(1)
Published: Nov. 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.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(8), P. 1672 - 1676
Published: Feb. 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.
The Journal of Organic Chemistry,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 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,
Journal Year:
2023,
Volume and Issue:
55(23), P. 3875 - 3894
Published: May 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
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
unknown
Published: July 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.
Organic Letters,
Journal Year:
2023,
Volume and Issue:
25(16), P. 2857 - 2862
Published: April 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,
Journal Year:
2023,
Volume and Issue:
13(9), P. 6261 - 6267
Published: April 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.
European Journal of Organic Chemistry,
Journal Year:
2024,
Volume and Issue:
27(19)
Published: Jan. 11, 2024
Abstract
Vinylcyclopropanes
(VCPs)
are
important
building
blocks
with
multifaceted
reactivity.
Catalytic
asymmetric
ring
opening
of
vinylcyclopropanes
is
a
highly
efficient
process
to
access
valuable
chiral
molecules
diverse
functionalities
that
can
be
further
functionalized
for
series
synthetic
purposes.
VCPs
very
well‐known
substrates
cycloaddition
reactions
and
this
chemistry
has
been
widely
explored.
On
the
contrary,
despite
enormous
potential,
development
new
innovative
strategies
catalytic,
somewhat
underdeveloped.
Recently,
several
significant
examples
have
emerged
in
literature
various
both
activated
unactivated
involve
transition
metal
catalysis.
These
developments
relevant
additions
vinylcyclopropane
chemistry.
In
review,
we
aim
summarize
all
catalytic
transformations
reported
till
date
provide
comprehensive
analysis
these
research
outcomes.
Chemical Communications,
Journal Year:
2024,
Volume and Issue:
60(25), P. 3441 - 3444
Published: Jan. 1, 2024
A
Zn(
ii
)-catalyzed
(3+2)-annulation
of
diaziridines
with
DA
aziridines
has
been
accomplished
via
1,4-hydride
shift
to
furnish
imidazo[1,5-
b
]pyrazole-4,4-dicarboxylates
under
mild
reaction
conditions.
