We
report
a
metal-free
iodosulfonylation
of
alkynes
in
water
at
room
temperature,
which
efficiently
produces
(
E
)-β-iodovinyl
sulfones
good
to
excellent
yields
with
high
regio-
and
stereoselectivity.
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: April 16, 2024
Abstract
The
past
century
has
witnessed
a
large
number
of
reports
on
the
Z
/
E
isomerization
alkenes.
However,
vast
majority
them
are
still
limited
to
di-
and
tri-substituted
stereospecific
tetrasubstituted
alkenes
remains
be
an
underdeveloped
area,
thus
lacking
in
stereodivergent
synthesis
axially
chiral
Herein
we
report
atroposelective
alkene
analogues
by
asymmetric
allylic
substitution-isomerization,
followed
their
via
triplet
energy
transfer
photocatalysis.
In
this
regard,
N
-vinylquinolinones
is
achieved
efficiently.
Mechanistic
studies
indicate
that
benzylic
radical
generation
distribution
two
key
factors
for
preserving
enantioselectivities
compounds.
Journal of the American Chemical Society,
Journal Year:
2021,
Volume and Issue:
143(45), P. 19078 - 19090
Published: Nov. 4, 2021
We
report
the
development
of
a
method
to
diastereoselectively
access
tetrasubstituted
alkenes
via
nickel-catalyzed
Suzuki-Miyaura
cross-couplings
enol
tosylates
and
boronic
acid
esters.
Either
diastereomeric
product
was
selectively
accessed
from
mixture
tosylate
starting
material
diastereomers
in
convergent
reaction
by
judicious
choice
ligand
conditions.
A
similar
protocol
also
enabled
divergent
synthesis
each
isomer
diastereomerically
pure
tosylates.
Notably,
high-throughput
optimization
monophosphine
ligands
guided
chemical
space
analysis
kraken
library
ensure
diverse
selection
examined.
Stereoelectronic
results
provided
insight
into
requirements
for
reactive
selective
this
transformation.
The
synthetic
utility
optimized
catalytic
system
then
probed
stereoselective
various
alkenes,
with
yields
up
94%
ratios
99:1
Z/E
93:7
E/Z
observed.
Moreover,
detailed
computational
experimental
mechanistic
studies
key
insights
nature
underlying
isomerization
process
impacting
selectivity
cross-coupling.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(14), P. 10167 - 10176
Published: March 27, 2024
The
π-bond
enrichment
frameworks
not
only
serve
as
a
crucial
building
block
in
organic
synthesis
but
also
assume
pivotal
role
the
fields
of
materials
science,
biomedicine,
photochemistry,
and
other
related
disciplines
owing
to
their
distinctive
structural
characteristics.
incorporation
various
substituents
into
C═C
double
bonds
tetrasubstituted
alkenes
is
currently
highly
significant
research
area.
However,
with
diverse
on
poses
challenge
achieving
stereoselectivity.
Here,
we
reported
an
efficient
convergent
route
Cu-catalyzed
borylalkynylation
both
symmetrical
unsymmetrical
1,3-diynes,
B2pin2,
acetylene
bromide
construction
boronated
phenyldiethynylethylene
(BPDEE)
derivatives
excellent
chemo-,
stereo-,
regioselectivities.
BPDEE
could
transform
novel
π-conjugated
gem-diphenyldiethynylethylene
(DPDEE),
vinylphenyldiethynylethylene
(VPDEE),
phenyltriethynylethylene
(PTEE)
by
stepwise
process,
which
provides
flexible
platform
for
complex
that
were
difficult
synthesize
previous
methods.
initial
optical
characterization
revealed
synthesized
molecules
exhibited
aggregation-induced
emission
(AIE)
properties,
further
establishes
groundwork
future
applications
enriches
advances
field
functional
research.
Accounts of Chemical Research,
Journal Year:
2024,
Volume and Issue:
57(5), P. 726 - 738
Published: Feb. 22, 2024
ConspectusBiologically
active
compounds
and
pharmaceutically
relevant
intermediates
often
feature
sterically
congested
stereogenic
centers,
in
particular,
carbon
stereocenters
that
are
either
tertiary
tetrasubstituted
ones
or
quaternary
nature.
Synthons
comprise
such
bulky
structurally
complex
core
units
of
high
synthetic
value
represent
important
incentives
for
communities
connected
to
drug
discovery
development.
Streamlined
approaches
give
access
a
diverse
set
incorporating
acyclic
relatively
limited,
though
vital.
They
enable
further
exploration
three-dimensional
entities
can
be
designed
implemented
programs,
thereby
extending
the
pool
molecular
properties
is
inaccessible
flat
molecules.
However,
lack
modular
substrates
particular
areas
chemical
space
inspired
us
consider
functionalized
heterocycles
known
as
cyclic
carbonates
carbamates
productive
way
create
crowded
alkenes
stereocenters.In
this
Account,
we
describe
major
approximations
followed
over
course
8
years
using
transition
metal
(TM)
catalysis
an
instrument
control
stereochemical
various
allylic
propargylic
substitution
processes
related
transformations.
Allylic
reactions
empowered
by
Pd-catalysis
utilizing
variety
nucleophiles
discussed,
with
amination
being
seed
all
combined
work.
These
procedures
build
on
vinyl-substituted
(VCCs)
simple
easy-to-access
precursors
highly
nature
compared
synthetically
limited
vinyl
oxiranes.
Overall
these
decarboxylative
conversions
take
place
"linear"
"branched"
regioselectivities
ligand
controlled
offer
wide
scope
functional
scaffolds.
Alternative
approaches,
including
dual
TM/photocatalyzed
transformations,
allowed
expand
repertoire
challenging
stereoselective
conversions.
This
was
achieved
through
key
single-electron
pathways
via
formal
umpolung
intermediates,
resulting
new
types
carbon–carbon
bond
formation
significantly
expanding
reactions.Heterocyclic
substrate
variants
have
triple
groups
were
also
difficult-to-promote
TM
catalysis.
In
processes,
Nishibayashi
laboratory
their
seminal
findings
area,
discovered
reactivity
patterns.
provided
range
different
stereodefined
building
blocks
1,2-diborylated
1,3-dienes
α-allenols
under
Cu-
Ni-catalysis.
realm,
use
lactone-derived
gives
elusive
chiral
γ-amino
acids
lactams
stereofidelity
good
structural
diversity.Apart
from
efforts,
elucidated
some
pertinent
mechanistic
manifolds
operative
transformations
better
understand
limitations
opportunities
specifically
synthons.
We
both
theoretical
experimental
investigations
lead
several
unexpected
outcomes
terms
enantioinduction
models,
catalyst
preactivation,
intimately
rationales
observed
selectivity
profiles.
The
work
communicated
offers
insight
into
unique
carbonates/carbamates
acting
privileged
precursors.
It
may
inspire
other
members
widen
toward
novel
added
development
academic
commercial
settings.
ACS Catalysis,
Journal Year:
2023,
Volume and Issue:
13(20), P. 13414 - 13422
Published: Oct. 3, 2023
The
conversion
of
feedstock
materials
into
useful
chemical
compounds
through
feasible
processes
is
highly
sought
after
from
both
industrial
and
environmental
perspectives.
In
this
study,
we
developed
a
simple
scalable
protocol
for
synthesizing
aldehydes,
ketones,
amides
abundant
raw
materials,
such
as
alkanes,
alkenes,
carboxylic
acids.
Using
photoactive
mesoporous
graphitic
carbon
nitride
catalyst
(mpg-CN)
molecular
oxygen,
successfully
transformed
over
60
substrates
in
good
yield
selectivity.
This
method
suitable
the
late-stage
modification
existing
drug
molecules
their
corresponding
carbonyl
derivatives
can
provide
direct
access
to
intermediates
or
oxidative
decomposition
degradation
products
important
understanding
biological
pathways
development.
Additionally,
our
applicable
large-scale
preparation,
mpg-CN
be
recycled
without
significant
loss
catalytic
activity
Comprehensive
experiments,
including
labeled
oxygen
studies,
support
photo-oxidative
mechanism.
ACS Catalysis,
Journal Year:
2023,
Volume and Issue:
13(10), P. 6795 - 6803
Published: May 3, 2023
Herein,
we
report
a
nickel-catalyzed
asymmetric
three-component
trans-dicarbofunctionalization
of
β-substituted
α-naphthyl
propargylic
alcohols
using
readily
available
aryl
and
benzyl
halides
as
the
coupling
partners
under
reductive
conditions.
This
cross-electrophile
strategy
enables
synthesis
various
axially
chiral
allylic
bearing
tetrasubstituted
olefinic
unit
in
complete
regio-
E
selectivity,
well
high
enantiocontrol.
Relying
on
hydroxyl
group
functional
handle,
such
structural
motifs
are
successfully
derivatized
into
diverse
functional-group-rich
alkenes.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
63(15)
Published: Feb. 7, 2024
Abstract
A
regioselective
silylium‐ion‐promoted
thiosilylation
of
internal
C−C
triple
bonds
with
control
over
the
double
bond
geometry
is
described.
Both
a
C(sp
2
)−S
and
)−Si
are
formed
trans
relationship
in
this
two‐component
reaction
an
alkyne
thiosilane.
The
resulting
orthogonally
functionalized
can
be
chemoselectively
defunctionalized
or
further
processed
by
cross‐coupling
reactions
alkene
configuration
retained.
procedure
also
applicable
to
regio‐
diastereoselective
terminal
allenes
arrive
at
allylic
thioethers
containing
vinylsilane
unit.
These
involve
electrophilic
activation
S−Si
reagent,
both
silylated
thiophenol
even
alkylthiol
derivative,
situ‐generated
carbocation
intermediate.
catalytic
cycle
maintained
bissilylated
aryl‐
alkylsulfonium
ion
as
shuttle
for
cationic
silicon
electrophile.
Its
independent
preparation
structural
characterization
X‐ray
diffraction
reported.
The Journal of Organic Chemistry,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 25, 2025
The
Z-
or
E-selective
syntheses
of
tetrasubstituted
olefins
present
big
challenges.
Tremendous
efforts
are
ongoing
to
overcome
this
issue,
especially
for
acyclic
structures.
In
work,
an
E-stereoselective
synthetic
method
through
tandem
reaction
1,4-Michael
addition
3-acetyl-4-phenyl-1-oxaspiro[4.5]deca-3,6,9-triene-2,8-dione
with
amine,
C-C
bond
breakage,
and
proton
transfer
by
intermolecular
hydrogen
bonds
was
revealed
excellent
atom
economy
without
catalysts
additives.
A
diverse
set
E-tetrasubstituted
were
obtained
in
43%
93%
yields
functional
group
tolerance
late-stage
modifications
complex
drug
molecules.
mechanism
proposed
based
on
the
deuterium-labeling
experiment
density
theory
(DFT)
calculation.