Synlett,
Journal Year:
2022,
Volume and Issue:
34(04), P. 293 - 300
Published: Nov. 20, 2022
Abstract
The
reassembly
of
unsaturated
C–C
bonds
has
attracted
widespread
attention
from
synthetic
chemists
due
to
its
advantages
unique
reactivity,
easy
handling,
and
high
atom
step
economies.
We
recently
explored
a
cutting/insertion
cascade
as
means
introducing
new
C1
source
constructing
functionalized
1,4-keto
aldehyde
2H-furan
derivatives
through
cyclopropanation
enamines
with
various
carbene
precursors
subsequent
ring-opening
reactions
in
situ.
Aminocyclopropanes
are
believed
be
involved
key
intermediates
these
transformations.
This
Synpacts
article
outlines
our
recent
contributions
this
increasingly
important
research
area.
1
Introduction
2
Cleavage
Enamine
C=C
Double
Bonds
Hydrolysis
1,4-Keto
Aldehydes
3
Cyclization
2H-Furans
4
Ynone/Ynoate
C≡C
Triple
5
Conclusion
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(29)
Published: May 22, 2023
Chiral
biscyclopropanes
are
an
important
skeleton
in
many
bioactive
molecules.
However,
there
few
routes
to
synthesize
these
molecules
with
high
stereoselectivity
due
the
nature
of
multiple
stereocenters.
Herein,
we
report
first
example
Rh2
(II)-catalyzed
enantioselective
synthesis
bicyclopropanes
alkynes
as
dicarbene
equivalents.
The
4-5
vicinal
stereocenters
and
2-3
all-carbon
quaternary
centers
were
constructed
excellent
stereoselectivity.
This
protocol
features
efficiency
functional
group
tolerance.
Moreover,
was
also
extended
cascaded
cyclopropanation/cyclopropenation
stereoselectivities.
In
processes,
both
sp-carbons
alkyne
converted
into
stereogenic
sp3
-carbons.
Experimental
density
theory
(DFT)
calculations
revealed
that
cooperative
weak
hydrogen
bonds
between
substrates
dirhodium
catalyst
may
play
key
roles
this
reaction.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(38)
Published: June 18, 2024
Described
herein
is
a
dirhodium(II)-catalyzed
silylation
of
propargyl
esters
with
hydrosilanes,
using
tertiary
amines
as
axial
ligands.
By
adopting
this
strategy,
range
versatile
and
useful
allenylsilanes
can
be
achieved
good
yields.
This
reaction
not
only
represents
S
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 18, 2025
Cereblon
E3
ligase
modulatory
drugs
(CELMoDs)
can
be
used
to
target
proteins
and
mark
them
for
proteasomal
degradation
by
recruiting
cereblon
(CRBN),
the
substrate
receptor
of
CRL4CRBN
ubiquitin
complex.
Modifications
stereochemistry
regiochemistry
distal
functionality
on
CELMoDs
have
been
shown
large
effects
activity
selectivity;
however,
methods
allowing
rapid
selective
introduction
enantioenriched
moieties
are
rare.
Herein,
we
report
that
classical
CRBN-binding
glutarimide
cores
successfully
derivatized
aryl
diazoacetates.
These
diazo
derivatives,
when
in
presence
a
dirhodium
catalyst,
undergo
high-yielding
highly
enantioselective
C–H
functionalization
hydrocarbons
cyclopropanation
styrene.
products
create
not
only
molecular
glue
degrader-like
compounds
but
also
intermediates
elaborated
into
effective
bifunctional
ligand-directed
degraders.
Our
findings
highlight
both
effectiveness
catalysis
drug
discovery
context
new
method
preparing
diverse
stereoenriched
glutarimide-containing
compounds.
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 10, 2025
Herein,
we
disclose
the
discovery
and
development
of
a
site-,
regio-,
diastereo-,
enantioselective
aryl
C-H
bond
cyclopropylation
using
diazomethyl
hypervalent
iodine
reagents,
styrenes,
paddlewheel
dirhodium
carboxylate
catalysts.
A
key
aspect
this
work
was
catalytic
generation
chiral
Rh(II)
carbene
through
an
electrophilic
aromatic
substitution
with
carbynoids.
The
strategy
allows
construction
cyclopropane
rings
bonds
from
feedstocks
drug
molecules
promises
to
reach
unexplored
"cyclopropanated"
chemical
space
highly
difficult
by
current
strategies.
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 16, 2025
In
recent
years,
additives
that
modulate
both
reactivity
and
selectivity
in
rhodium-catalyzed
reactions
of
aryldiazoacetates
have
become
increasingly
prominent.
1,1,1,3,3,3-Hexafluoroisopropanol
(HFIP)
has
been
shown
to
a
profound
effect
on
rhodium
carbene
selectivity,
especially
enabling
cyclopropanation
the
presence
various
nucleophilic
poisons.
HFIP
also
variable
influence
enantioselectivity
catalyzed
by
chiral
dirhodium
tetracarboxylates,
this
study
examines
fundamental
properties
carbene/HFIP
system
through
experimentation,
density
functional
theory
(DFT),
molecular
dynamics
(MD)
simulations.
These
studies
revealed
C4-symmetric
bowl-shaped
catalysts,
which
previously
considered
be
relatively
rigid,
experience
far
greater
flexibility
hydrogen
bonding
media,
resulting
distortion
catalysts.
explain
why
even
though
majority
catalysts
drop
HFIP,
some
such
as
Rh2(TCPTAD)4,
lead
switch
enantioselectivity,
whereas
others,
Rh2(NTTL)4,
considerably
enhanced
enantioselectivity.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(31), P. 6556 - 6561
Published: July 31, 2024
Cross-electrophile
coupling
reactions
that
forge
C(sp3)–C(sp3)
bonds
are
strategic
methods
for
the
synthesis
of
molecules
with
high
F(sp3),
yet
very
few
employ
electrochemical
conditions
as
necessary
reductant.
Herein,
we
report
an
intramolecular
cross-electrophile
reaction
1,3-diol
derivatives
to
access
aliphatic
and
aryl
cyclopropanes,
including
spirocyclic
fused
bicyclic
cyclopropanes.
The
scalable
(eXEC)
employs
a
nonsacrificial
anode
in
undivided
cell.
Unprecedented
diazoacetate
N
-heteroarenium
salts
are
synthesized
and
participate
in
catalytic
[2
+
1]
cycloadditions
[2,3]-sigmatropic
rearrangements,
providing
facile
access
to
otherwise
difficult-to-obtain
multi-functionalized
-heterocycles.
