Synlett,
Год журнала:
2022,
Номер
33(18), С. 1819 - 1825
Опубликована: Окт. 14, 2022
Abstract
Vicinal
dihalides
not
only
emerge
as
reactive
intermediates
in
synthetic
organic
chemistry,
but
also
are
extensively
existing
bioactive
marine
natural
products.
The
dihalogenation
of
alkenes
is
the
most
direct
and
effective
method
for
synthesis
vicinal
dihalides.
Because
there
always
an
exchange
process
between
chiral
haloniums
unreacted
olefins
to
cause
racemization,
development
catalytic
enantioselective
great
difficulty.
Recently,
progress
has
been
made
asymmetric
manner.
However,
a
lack
related
review
discussions
mechanisms
reaction
systems.
This
aimed
at
summarizing
alkenes,
including
1,2-dichlorination,
1,2-dibromination,
1,2-difluorination,
which
expected
encourage
more
researchers
participate
this
field.
1
Introduction
2
Enantioselective
1,2-Dichlorination
1,2-Dibromination
Alkenes
2.1
Chiral-Boron-Complex-Promoted
2.2
Organocatalytic
Asymmetric
2.3
Chiral-Titanium-Complex-Catalyzed
1,2-Dihalogenation
3
Chiral-Iodide-Catalyzed
Oxidative
1,2-Difluorination
4
Summary
Outlook
Chemical Communications,
Год журнала:
2023,
Номер
59(89), С. 13309 - 13312
Опубликована: Янв. 1, 2023
This
study
describes
an
iron-catalyzed
divergent
oxidation
of
styrene
into
β-hydroxylmethylketone
and
ketone
under
photo-irradiation.
divergence
is
ascribed
to
the
use
with
various
substituents.
More
importantly,
methanol
oxidized
formaldehyde
in
reaction
serves
as
a
C1
synthon.
Mechanism
investigations
show
that
initiated
by
oxidative
SET
transfer
cation
radical.
The
pathway
undergoes
HAT
β-hydride
elimination
well
concerted
cyclization.
Particularly,
several
drug-like
molecules,
such
melperone
analogue,
lenperone
haloperidol
are
synthesized.
In
addition,
this
method
also
applicable
synthesis
natural
product
(R)-atomoxetine.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(30)
Опубликована: Май 2, 2024
Abstract
The
1,3‐difunctionalization
of
unactivated
alkenes
is
an
under‐explored
transformation
that
leads
to
moieties
are
otherwise
challenging
prepare.
Herein,
we
report
a
hypervalent
iodine‐mediated
1,3‐difluorination
homoallylic
(aryl)
ethers
give
unreported
1,3‐difluoro‐4‐oxy
groups
with
moderate
excellent
diastereoselectivity.
proceeds
through
different
mode
reactivity
for
1,3‐difunctionalization,
in
which
regioselective
addition
fluoride
opens
transiently
formed
oxonium
intermediate
rearrange
alkyl
chain.
optimized
protocol
scalable
and
shown
proceed
well
variety
functional
substitution
on
the
alkenyl
chain,
hence
providing
ready
access
this
fluorinated,
conformationally
controlled
moiety.
Vicinal
dihaloalkane
is
extremely
important
structural
unit,
and
dihalogenation
of
alkene
provides
a
prospective
way
access
to
such
moiety.
Despite
more
than
century
development,
it
still
challenging
necessary
avoid
the
use
toxic
harmful
halogenating
reagents
develop
efficient,
sustainable,
broader
functional
group
tolerant
skeleton-compatible
strategies.
We
report
herein
first
metal-free
protocol
for
radical
vicinal
dichlorination
dibromination
by
photocatalytic
energy
transfer
strategy
using
N-halo-benzophenonimine
(NXB)
as
readily
accessible
reagents.
This
approach
undergoes
addition
halogen
atom
derived
from
N-X
bond
photolysis
NXB
onto
olefins,
followed
halogen-atom
process.
features
facile
operation,
mild
reaction
conditions,
wide
tolerance,
compatible
with
large
complex
scaffolds
unsaturated
fatty
acid,
terpenes
steroid,
alkaloid,
sugar,
amino
peptide.
Asian Journal of Organic Chemistry,
Год журнала:
2023,
Номер
12(6)
Опубликована: Май 2, 2023
Abstract
This
work
presents
a
photo‐redox
vicinal
dichlorination
of
acrylamides
using
naturally
abundant
chlorine
source
(FeCl
3
).
The
LMCT
FeCl
is
responsible
for
the
radical
inducement,
while
tetra‐
n
‐butylammonium
decatungstate
(TBADT)
catalytic
system
enhanced
process.
method
exhibits
extraordinarily
mild
conditions,
not
requiring
external
ligands
and
low
E
factors,
which
enables
scalable
synthesis.
Chemical Science,
Год журнала:
2021,
Номер
12(22), С. 7746 - 7757
Опубликована: Янв. 1, 2021
Ab
initio
dynamics
of
the
halolactonization
reaction
provide
insights
into
diastereoselectivity
reaction.
Noncovalent
interactions
between
substrate,
halogen
source
and
solvent
are
revealed
to
direct
formation
syn-product.
Synlett,
Год журнала:
2024,
Номер
35(16), С. 1906 - 1908
Опубликована: Март 20, 2024
Abstract
An
attempted
aryl
selenium-catalyzed
formation
of
cis-chlorohydrins
from
alkenes
was
unsuccessful
but
led
to
an
electrochemical
investigation
for
the
trans-selective
chloroformyloxylation
cyclic
and
acyclic
in
moderate
good
yields.
Interestingly,
when
1,1-disubstituted
were
used,
corresponding
vinyl
chloride
derivatives
obtained,
application
1-phenylcyclohex-1-ene
allyl
derivative.
Journal of Lipid Research,
Год журнала:
2024,
Номер
65(7), С. 100572 - 100572
Опубликована: Май 30, 2024
Contrast-enhanced
computed
tomography
offers
a
nondestructive
approach
to
studying
adipose
tissue
in
3D.
Several
contrast-enhancing
staining
agents
(CESAs)
have
been
explored,
whereof
osmium
tetroxide
(OsO
European Journal of Organic Chemistry,
Год журнала:
2024,
Номер
27(29)
Опубликована: Июнь 11, 2024
Abstract
We
established
a
straightforward
electrochemical
dihalogenation
(F,
Cl,
and
Br)
process
for
gem
‐difluoroalkenes.
This
reaction
exhibits
broad
functional
group
tolerance
has
been
effectively
utilized
in
the
construction
of
complex
molecules.
The
subsequent
synthetic
transformations
products
have
highlighted
adaptable
nature
dihalogenated
compounds,
demonstrating
their
potential
application
drug
discovery
investigation
innovative
materials.
effective
utilization
product
18
F‐labeling
represents
novel
approach
generating
highly
potent
F‐labeled
tracers.
European Journal of Organic Chemistry,
Год журнала:
2021,
Номер
2021(19), С. 2788 - 2791
Опубликована: Апрель 21, 2021
Abstract
The
weakly
coordinating
dianion
[B
12
Cl
]
2−
originates
from
a
family
of
carboranes
typically
reserved
for
application
in
coordination
chemistry.
Herein,
we
show
that
its
readily
accessible
Ag(I)
salt,
[Ag]
2
],
can
be
used
as
catalyst
the
PhICl
mediated
chlorination
arenes,
alkenes,
and
alkynes.
promising
activity
displayed
by
over
variety
commercially
available
sources
merits
incorporation
to
toolkit
commonly
screened
silver
catalysts
synthesis.
Advanced Synthesis & Catalysis,
Год журнала:
2021,
Номер
363(15), С. 3852 - 3858
Опубликована: Июнь 18, 2021
Abstract
Enantioselective
iodocycloetherifications
can
be
conducted
using
sterically
highly
demanding
BINOL‐based
phosphoric
acid
diesters
as
catalyst.
To
achieve
enantioselective
reactions,
cocatalysis
by
triphenylphosphine
selenide
is
necessary.
With
cocatalysis,
good
to
excellent
enantioselectivities
achieved
for
a
broad
range
of
substrates
catalyst
and
cocatalyst
loadings
low
1
mol
%.
The
itself
does
not
strongly
influence
diastereoselectivity,
but
leads
higher
reactivity
and,
in
combination
with
diester,
enantioselectivity.
magnified
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