Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
63(2)
Опубликована: Ноя. 28, 2023
This
report
describes
the
development
of
a
Zn(OTf)2
-mediated
method
for
converting
α-tertiary
haloamides
to
corresponding
fluorine-18
labelled
fluoroamides
with
no-carrier-added
[18
F]tetramethylammonium
fluoride.
1,5,7-Triazabicyclo[4.4.0]dec-5-ene
is
an
essential
additive
achieving
high
radiochemical
conversion.
Under
optimised
conditions,
radiofluorination
proceeds
at
sterically
hindered
tertiary
sites
in
conversions,
yields,
and
purities.
has
been
successfully
automated
applied
access
>200
mCi
(>7.4
GBq)
several
model
radiofluorides.
Mechanistic
studies
led
new,
nucleophilic
C-H
process
using
N-sulphonyloxyamide
substrates.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(11), С. 7191 - 7197
Опубликована: Март 5, 2024
Photoenzymatic
intermolecular
hydroalkylations
of
olefins
are
highly
enantioselective
for
chiral
centers
formed
during
radical
termination
but
poorly
selective
set
in
the
C–C
bond-forming
event.
Here,
we
report
evolution
a
flavin-dependent
"ene"-reductase
to
catalyze
coupling
α,α-dichloroamides
with
alkenes
afford
α-chloroamides
good
yield
excellent
chemo-
and
stereoselectivity.
These
products
can
serve
as
linchpins
synthesis
pharmaceutically
valuable
motifs.
Mechanistic
studies
indicate
that
formation
occurs
by
exciting
charge-transfer
complex
templated
protein.
Precise
control
over
orientation
molecules
within
potentially
accounts
observed
The
work
expands
types
motifs
be
prepared
using
photoenzymatic
catalysis.
ChemistryOpen,
Год журнала:
2020,
Номер
9(2), С. 100 - 170
Опубликована: Янв. 13, 2020
The
aim
of
this
review
is
to
highlight
the
rich
chemistry
α-haloamides
originally
mainly
used
discover
new
C-N,
C-O
and
C-S
bond
forming
reactions,
later
widely
employed
in
C-C
cross-coupling
reactions
with
C(sp3),
C(sp2)
C(sp)
coupling
partners.
Radical-mediated
transformations
bearing
a
suitable
located
unsaturated
has
proven
be
straightforward
alternative
access
diverse
cyclic
compounds
by
means
either
radical
initiators,
transition
metal
redox
catalysis
or
visible
light
photoredox
catalysis.
On
other
hand,
cycloadditions
α-halohydroxamate-based
azaoxyallyl
cations
have
garnered
significant
attention.
Moreover,
view
important
role
life
materials
science
difluoroalkylated
compounds,
wide
range
catalysts
been
developed
for
efficient
incorporation
difluoroacetamido
moieties
into
activated
as
well
unactivated
substrates.
Organic Letters,
Год журнала:
2021,
Номер
23(4), С. 1451 - 1456
Опубликована: Фев. 1, 2021
Oxindoles
and
β-lactams
are
attractive
structural
motifs
because
of
their
unique
biological
importance.
However,
the
fusion
two
moieties
featuring
3,3′-spirocyclic
scaffolds
is
a
challenging
task
in
organic
synthesis.
Herein
we
designed
novel
type
oxindole-based
azaoxyallyl
cation
synthons,
which
could
readily
participate
[3
+
1]
cyclization
with
sulfur
ylides.
With
this
protocol,
collection
3,3-spiro[β-lactam]-oxindoles
were
facilely
produced
up
to
94%
yield
perfect
diastereoselectivity.
Chemical Science,
Год журнала:
2024,
Номер
15(27), С. 10659 - 10667
Опубликована: Янв. 1, 2024
The
direct
activation
of
α-halo
carboxylic
acids
using
visible-light-mediated
photoredox
catalysis
facilitates
the
formation
bifunctional
radical
intermediates,
allowing
reactivity
toward
olefins
to
be
fine-tuned
by
varying
solvent
system.
Abstract
Compounds
bearing
mono-
and
dibromomethyl
groups
are
extensively
utilized
in
synthetic
medicinal
chemistry.
In
this
regard,
selective
debromination
of
readily
or
easily
accessible
tribromomethyl
compounds
offers
a
direct
efficient
method
to
access
those
two
moieties.
work,
we
introduced
Lewis
base–borane-mediated
hydrodebromination
via
ionic
radical
pathway.
Using
4-(dimethylamino)pyridine–borane
(DMAP-BH3)
as
hydride
donor,
monohydrodebromination
was
achieved
nucleophilic
substitution
by
hydride,
delivering
groups.
On
the
other
hand,
treatment
with
an
N-heterocyclic
carbene–borane
(NHC-BH2CN)
boryl
precursor
presence
dilauroyl
peroxide
(DLP)
initiator
afforded
monobromomethyl
through
consecutive
bromine
atom
abstractions
cleave
C–Br
bonds.
Various
group
acetamides
acetates
were
applied
developed
protocol,
showcasing
good
functional
tolerance
broad
substrate
scope.
ACS Catalysis,
Год журнала:
2025,
Номер
15(5), С. 3873 - 3881
Опубликована: Фев. 19, 2025
Herein,
we
report
the
reaction
development
and
mechanistic
studies
of
visible-light-driven
Cu-catalyzed
dechlorination
trichloroacetic
acid
for
highly
selective
formation
monochloroacetic
acid.
Visible-light-driven
transition
metal
catalysis
via
an
inner-sphere
pathway
features
dual
roles
species
in
photoexcitation
substrate
activation
steps,
a
detailed
understanding
their
is
crucial
further
light-driven
catalysis.
This
catalytic
method,
which
environmentally
desired
ascorbic
as
hydrogen
atom
source
water/ethanol
solvent,
can
be
applied
to
dehalogenation
variety
halocarboxylic
acids
amides.
Spectroscopic,
X-ray
crystallographic,
kinetic
have
revealed
mechanism
copper
photoexcitation,
thermal
first
C–Cl
bond,
excited-state
second
bond
chlorine
transfer.
