Organic Letters,
Journal Year:
2023,
Volume and Issue:
25(44), P. 7963 - 7967
Published: Nov. 2, 2023
A
Lewis-acid-promoted
domino
ring-opening
cyclization
of
readily
available
donor–acceptor
cyclopropanes
with
a
preinstalled
electrophilic
center,
embedded
in
donor
group,
to
functionalized
1,2-dihydronaphthalenes
is
reported
herein.
The
obtained
compounds
are
transformed
pharmacologically
attractive
bridged
tricyclic
esters
diastereospecific
manner.
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.
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
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.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(22), P. 8921 - 8925
Published: Nov. 1, 2021
A
catalyst-free
[4+3]-cycloaddition
reaction
of
N-aryl
sulfilimines
with
cyclobutenones
is
described,
which
provides
a
straightforward
protocol
for
synthesizing
1,5-dihydro-2H-benzo[b]azepin-2-ones
under
mild
conditions.
This
features
broad
substrate
scope
and
good
functional
group
tolerance
does
not
require
catalysts
or
additives.
Moreover,
using
N-pyridinyl
sulfilimine
as
the
substrate,
series
pyridoazepinones
have
also
been
prepared.
Organic Chemistry Frontiers,
Journal Year:
2023,
Volume and Issue:
10(8), P. 1948 - 1958
Published: Jan. 1, 2023
The
mechanism
and
stereoselectivity
of
the
Ni-catalyzed
[3
+
3]
annulation
between
donor–acceptor
cyclopropanes
(DACs)
diaziridines
were
rationalized
by
DFT
calculations.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 26, 2024
Catalytic
asymmetric
transformation
of
donor–acceptor
cyclopropanes
(DACs)
has
been
proven
to
be
a
highly
valuable
and
robust
strategy
construct
diverse
types
enantioenriched
molecules.
However,
the
use
1,1,2,2-tetrasubstituted
DACs
form
products
bearing
quaternary
stereocenters
remains
long-term
unsolved
challenge.
Here,
we
report
copper-catalyzed
aminative
ring
opening
tetrasubstituted
alkynyl
that
delivers
myriad
α-tertiary
amines
with
high
levels
enantioselectivities.
The
alkyne,
amine,
ester
moieties
within
enable
further
applications,
including
synthesis
bioactive
Mechanistic
studies
indicate
zwitterionic
intermediate
copper-acetylide
unit
plays
key
role
in
process,
which
represents
new
mode
for
achieving
catalytic
DACs.
The Journal of Organic Chemistry,
Journal Year:
2021,
Volume and Issue:
86(23), P. 16558 - 16572
Published: Nov. 15, 2021
A
ytterbium
triflate-catalyzed
diastereoselective
[3
+
2]
cycloaddition
of
quinoxalinones
with
donor-acceptor
cyclopropanes
and
cyclobutanes
is
described.
series
tetrahydropyrrolo-quinoxalinone
derivatives
were
obtained
in
high
yields
(up
to
96%)
excellent
diastereoselectivities
46:1).
Other
medicinally
important
heterocycles
like
benzoxazinone,
isoquinoxalinone,
dibenzoxazepine
also
suitable
for
the
desired
annulation
reaction.
The
current
method
applicable
scale-up
Further,
utility
this
reaction
demonstrated
by
synthesis
densely
functionalized
proline
derivatives.
Advanced Synthesis & Catalysis,
Journal Year:
2022,
Volume and Issue:
364(14), P. 2403 - 2415
Published: June 16, 2022
Abstract
We
report
a
procedure
for
the
multigram
synthesis
of
4‐(dimethylamino)pyridinium
azide,
stable,
non‐explosive,
low‐hygroscopic
source
azide
ion
soluble
in
both
protic
and
aprotic
organic
solvents.
In
ionic
liquid
media
this
reagent
was
shown
to
serve
as
safer
equivalent
toxic
unstable
hydrazoic
acid.
The
synthetic
utility
system
demonstrated
using
donor‐acceptor
cyclopropane
ring
opening
model
process.
General
procedures
furnishing
variety
dialkyl
(2‐azido‐2‐arylethyl)malonates
or
4‐azido‐4‐arylbutyrates,
depending
on
applied,
were
elaborated.
conversion
times
studied
cyclopropanes
established
providing
relative
reactivity
sequence.
application
conventional
nucleophilic
substitution,
oxirane
opening,
(3+2)‐cycloaddition
(thio)cyano
group
well
their
combinations
realized
telescopic
also
demonstrated.
magnified
image