ACS Catalysis,
Год журнала:
2024,
Номер
unknown, С. 17503 - 17509
Опубликована: Ноя. 13, 2024
A
synergistic
photoredox
and
palladium-catalyzed
1,3-acyloxyallylation
of
aryl
cyclopropanes
with
allyl
esters
has
been
developed.
Aryl
are
unprecedentedly
employed
as
radical
precursors
in
allylation
reactions
acting
bifunctional
reagents,
thereby
providing
acyloxy
groups
nucleophiles
the
moiety
a
scavenger
for
formation
benzylic
C(sp3)–C(sp3)
bonds.
This
redox-neutral
reaction
exhibits
100%
atom
economy
good
functional
group
tolerance
successfully
applied
to
late-stage
modification
pharmaceutical
derivatives.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(13)
Опубликована: Янв. 30, 2024
Abstract
Herein,
we
have
synthesized
multifunctionalized
2‐oxa‐3‐azabicyclo[3.1.1]heptanes,
which
are
considered
potential
bioisosteres
for
meta
‐substituted
arenes,
through
Eu(OTf)
3
‐catalyzed
formal
dipolar
[4π+2σ]
cycloaddition
of
bicyclo[1.1.0]butanes
with
nitrones.
This
methodology
represents
the
initial
instance
fabricating
bicyclo[3.1.1]heptanes
adorned
multiple
heteroatoms.
The
protocol
exhibits
both
mild
reaction
conditions
and
a
good
tolerance
various
functional
groups.
Computational
density
theory
calculations
support
that
mechanism
likely
involves
nucleophilic
addition
nitrones
to
bicyclo[1.1.0]butanes,
succeeded
by
an
intramolecular
cyclization.
synthetic
utility
this
novel
has
been
demonstrated
in
concise
synthesis
analogue
Rupatadine.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(24)
Опубликована: Апрель 13, 2024
Abstract
We
disclose
herein
a
novel
photoredox
and
cobalt
co‐catalyzed
ring‐opening/acceptorless
dehydrogenative
functionalization
of
mono‐donor
cyclopropanes.
This
sustainable
atom‐economic
approach
allows
the
rapid
assembly
wide
range
allylic
N,O
‐acyl‐acetal
derivatives.
The
starting
materials
are
readily
available
reaction
features
mild
conditions,
broad
substrate
scope,
excellent
functional
group
compatibility.
optimized
conditions
accommodate
assorted
cycloalkylamides
primary,
secondary,
tertiary
alcohols,
with
applications
in
late‐stage
pharmaceutically
relevant
compounds,
stimulating
further
utility
medicinal
chemistry.
Moreover,
selective
nucleophilic
substitutions
various
carbon
nucleophiles
were
achieved
one‐pot
fashion,
offering
reliable
avenue
to
access
some
cyclic
acyclic
Organic Letters,
Год журнала:
2024,
Номер
26(38), С. 8063 - 8068
Опубликована: Сен. 16, 2024
Pyridines
and
cyclopropanes
are
important
structural
units
in
chemistry.
Herein,
we
introduce
a
photoredox-catalyzed
approach
for
the
ring
opening
1,3-oxypyridylation
of
aryl
using
4-cyanopyridines
carboxylic
acids.
This
sequential
process
involves
single-electron
oxidation
cyclopropane,
leading
to
nucleophilic
radical
pyridylation
at
benzylic
position.
The
redox-neutral
reaction
exhibits
high
regioselectivity
under
mild
conditions,
offering
broad
substrate
scope
wide
applicability.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Окт. 16, 2024
The
carboamination
of
unsaturated
molecules
using
bifunctional
reagents
is
considered
an
attractive
approach
for
the
synthesis
nitrogen-containing
compounds.
However,
C-N
have
never
been
employed
in
cyclopropane.
In
this
study,
we
use
N-heterocyclic
carbene
(NHC),
N-benzoyl
saccharin,
as
a
reagent
and
photoredox
catalyst
dual-catalyzed
1,3-aminoacylation
NHCs
play
multiple
roles,
functioning
Lewis
base
catalysts
to
activate
bonds,
promoting
oxidative
quenching
process
PC*,
acting
efficient
acyl
radical
transfer
formation
C-C
bonds.
between
excited-state
PC*
NHC
adduct
key
photooxidation
generality
aryl
cyclopropanes.
Angewandte Chemie,
Год журнала:
2024,
Номер
136(13)
Опубликована: Янв. 30, 2024
Abstract
Herein,
we
have
synthesized
multifunctionalized
2‐oxa‐3‐azabicyclo[3.1.1]heptanes,
which
are
considered
potential
bioisosteres
for
meta
‐substituted
arenes,
through
Eu(OTf)
3
‐catalyzed
formal
dipolar
[4π+2σ]
cycloaddition
of
bicyclo[1.1.0]butanes
with
nitrones.
This
methodology
represents
the
initial
instance
fabricating
bicyclo[3.1.1]heptanes
adorned
multiple
heteroatoms.
The
protocol
exhibits
both
mild
reaction
conditions
and
a
good
tolerance
various
functional
groups.
Computational
density
theory
calculations
support
that
mechanism
likely
involves
nucleophilic
addition
nitrones
to
bicyclo[1.1.0]butanes,
succeeded
by
an
intramolecular
cyclization.
synthetic
utility
this
novel
has
been
demonstrated
in
concise
synthesis
analogue
Rupatadine.
The Journal of Organic Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Фев. 19, 2025
A
novel
[3+3]
cyclization
reaction
between
phenol
and
hydrazone
was
successfully
developed
under
electrochemically
driven
conditions.
This
provided
access
to
a
diverse
array
of
1,3,4-oxadiazinane
compounds
in
consistently
high
yields,
reaching
up
87%.
Notably,
the
exhibited
remarkable
tolerance
toward
broad
spectrum
both
substrates,
underscoring
its
versatility.
Moreover,
protocol
distinguished
itself
by
exceptional
atom
step
economy,
facilitating
efficient
construction
functionalized
1,3,4-oxadiazines.
The
synthetic
utility
this
approach
further
exemplified
scalability,
as
demonstrated
gram-scale
reactions,
substrate
scope.
Abstract
Over
the
last
decade,
there
have
been
notable
advances
in
field
of
ring
opening
reaction
numerous
cyclopropane
derivatives
under
metal‐free
conditions
including
donor–acceptor
cyclopropanes,
acceptor‐activated
alkylidenecyclopropanes,
cyclopropyl
alcohols,
and
vinylidenecyclopropanes.
This
review
article
aims
to
offer
a
comprehensive
overview
on
cleavage
reactions
cyclopropanes
using
Bronsted
Lewis
acids,
organic
inorganic
bases,
TCT‐DMF,
ionic
liquids
etc.
Photoinduced
catalyst‐free
are
also
accentuated
this
review.
Here,
we
present
a
new
approach
for
the
activation
of
donor-acceptor
cyclopropanes
in
ring-opening
reactions,
which
does
not
require
use
Lewis
or
Brønsted
acid
as
catalyst.
Donor-acceptor
containing
phenolic
group
donor
undergo
deprotonation
and
isomerization
to
form
corresponding
quinone
methides.
This
innovative
strategy
was
applied
achieve
(4
+
1)-annulation
with
sulfur
ylides,
affording
functionalized
dihydrobenzofurans.
Additionally,
generated
Organic Letters,
Год журнала:
2024,
Номер
26(10), С. 2085 - 2090
Опубликована: Март 5, 2024
In
this
paper,
we
describe
a
Re2O7-mediated
ring-opening
arylation
of
unactivated
arylcyclopropane
because
its
functionalization
with
various
arenes
via
Friedel–Crafts-type
reactivity.
This
protocol
allows
facile
access
to
functionalized
1,1-diaryl
alkanes
and
is
characterized
by
broad
substrate
scope,
mild
reaction
conditions,
high
efficiency,
atom
economy.
Both
density
functional
theory
calculations
deuterium
labeling
experiments
were
carried
out
justify
the
indispensable
role
HFIP
in
transformation
pointed
ring
opening
being
rate-determining
step.
