Chemistry - A European Journal,
Год журнала:
2023,
Номер
30(10)
Опубликована: Дек. 13, 2023
A
novel
method
to
prepare
asymmetric
amine
ethers
is
reported.
Tertiary
alcohol
hydrogen
sulfate
intermediates
are
prepared
through
a
reactive
distillation
process,
followed
by
the
transesterification
process
afford
eventually
ethers.
Experiments
and
DFT
calculations
revealed
essential
roles
group
plays
in
highly
selective
monoesterification
process.
This
clean
tolerant
towards
various
functional
groups
with
good
yields
under
mild
condition,
which
obviously
superior
compared
conventional
processes.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(7), С. 3861 - 3868
Опубликована: Фев. 9, 2023
A
visible-light
photoredox-catalyzed
method
is
reported
that
enables
the
coupling
between
benzylic
C-H
substrates
and
N-H
azoles.
Classically,
medicinally
relevant
Molecules,
Год журнала:
2023,
Номер
28(16), С. 6127 - 6127
Опубликована: Авг. 18, 2023
The
functionalisation
of
C–H
bonds
has
been
an
enormous
achievement
in
synthetic
methodology,
enabling
new
retrosynthetic
disconnections
and
affording
simple
equivalents
for
synthons.
Hydrogen
atom
transfer
(HAT)
is
a
key
method
forming
alkyl
radicals
from
substrates.
Classic
reactions,
including
the
Barton
nitrite
ester
reaction
Hofmann–Löffler–Freytag
reaction,
among
others,
provided
early
examples
HAT.
However,
recent
developments
photoredox
catalysis
electrochemistry
have
made
HAT
powerful
tool
capable
introducing
wide
range
functional
groups
into
bonds.
Moreover,
greater
mechanistic
insights
stimulated
development
increasingly
site-selective
protocols.
Site-selectivity
can
be
achieved
through
tuning
electron
density
at
certain
using
additives,
judicious
choice
reagent,
solvent
system.
Herein,
we
describe
latest
methods
functionalizing
C–H/Si–H/Ge–H
indirect
between
2018–2023,
as
well
critical
discussion
reagents,
aspects,
substrate
scopes,
background
contexts
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Авг. 21, 2024
We
disclose
a
benzylic
C-H
oxidative
coupling
reaction
with
alcohols
that
proceeds
through
synergistic
deprotonation,
halogenation
and
substitution
sequence.
The
combination
of
tert-butoxide
bases
2-halothiophene
halogen
oxidants
enables
the
first
general
protocol
for
generating
using
benzyl
halides
deprotonative
pathway.
In
contrast
to
existing
radical-based
methods
functionalization,
this
process
is
guided
by
acidity
trends.
This
gives
rise
new
synthetic
capabilities,
including
ability
functionalize
diverse
methyl(hetero)arenes,
tolerance
oxidizable
nucleophilic
functional
groups,
precision
site-selectivity
polyalkylarenes
use
double
etherification
controllably
oxidize
methylarenes
benzaldehydes.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
63(29)
Опубликована: Апрель 24, 2024
Abstract
Methods
enabling
the
broad
diversification
of
C(sp
3
)−H
bonds
from
a
common
intermediate
are
especially
valuable
in
chemical
synthesis.
Herein,
we
report
site‐selective
(
N
‐phenyltetrazole)thiolation
aliphatic
and
(hetero)benzylic
using
commercially
available
disulfide
to
access
‐phenyltetrazole
thioethers.
The
thioether
products
readily
elaborated
diverse
fragment
couplings
for
C−C,
C−O,
or
C−N
construction.
C−H
functionalization
proceeds
via
radical‐chain
pathway
involving
hydrogen
atom
transfer
by
electron‐poor
‐phenyltetrazolethiyl
radical.
Hexafluoroisopropanol
was
found
be
essential
reactions
thiolation,
with
computational
analysis
consistent
dual
bonding
radical
imparting
increased
electrophilicity
facilitate
transfer.
Substrate
is
limiting
reagent
all
cases,
reaction
displays
an
exceptional
functional
group
tolerance
well
suited
applications
late‐stage
diversification.
ACS Catalysis,
Год журнала:
2024,
Номер
14(10), С. 8005 - 8012
Опубликована: Май 9, 2024
We
report
intra-
and
intermolecular
γ-amino
C(sp3)–H
functionalization
of
aliphatic
amines
using
a
vinylsulfone-based
HAT
(hydrogen
atom
transfer)
auxiliary
triple
catalysis,
which
is
composed
photoredox,
cobalt,
Brønsted
acid
catalysts
under
visible
light
irradiation.
The
process
accomplishes
four
elementary
steps:
(i)
electrophilic
carbon-centered
radical
formation
on
the
via
MHAT
(metal
hydride
hydrogen
reaction,
(ii)
generation
through
1,6-HAT
(iii)
single-electron
oxidation
to
carbocation
equivalents,
(iv)
nucleophilic
substitution
with
internal
or
external
nucleophiles.
As
result,
this
afforded
γ-amino-functionalized
products,
such
as
azetidines,
1,3-diamine,
1,3-aminoalcohol
derivatives.
European Journal of Organic Chemistry,
Год журнала:
2023,
Номер
27(11)
Опубликована: Дек. 21, 2023
Abstract
Mono
and
dichloro‐substituted
organic
molecules
are
shown
to
possess
significant
roles
in
various
fields,
especially
medicinal
chemistry.
One
approach
synthesizing
these
compounds
involves
the
selective
dechlorination
of
easily
prepared
trichloromethyl
compounds.
Nevertheless,
developing
a
practical
that
allows
mono‐
dihydrodechlorination
is
challenging
task.
Herein,
we
introduced
method
for
trichloroacetamides
acetates
which
was
promoted
by
two
different
Lewis
base‐boryl
radicals.
Accordingly,
4‐dimethylaminopyridine
(DMAP)‐borane
enabled
mono‐substitution
chlorine
atom
hydrogen
while
dihydro‐substitution
atoms
N
‐heterocyclic
carbene
(NHC)‐boryl
radical.
Using
deuterated
base‐borane
as
deuterium
source,
dideuterodechlorination
were
also
successfully
took
place.
This
protocol
features
broad
substrate
scope
operates
under
mild
reaction
conditions.
Organic Letters,
Год журнала:
2024,
Номер
26(20), С. 4286 - 4291
Опубликована: Май 9, 2024
Represented
herein
is
a
simple
thiol
identified
as
an
effective
precursor
to
photochemically
form
carbocation.
Thanks
the
thiyl
radical
rapid
transformation
disulfide,
which
serves
not
only
stabilize
generated
but
also
allow
second
electron
transfer
The
resulting
carbocations,
including
primary
benzylic,
secondary,
and
tertiary
can
smoothly
couple
with
nitrogen,
oxygen,
carbon
nucleophilic
coupling
partners
well
complex
drug
molecules,
accompanied
by
elemental
sulfur
formation
in
air.
Reaction Chemistry & Engineering,
Год журнала:
2024,
Номер
9(11), С. 2963 - 2974
Опубликована: Янв. 1, 2024
Wirelessly
powering
μLEDs
within
packed
bed
reactors
enables
scalable,
continuous,
green
chemical
manufacturing
by
overcoming
classical
light
penetration
limits.
We
disclose
a
benzylic
C–H
oxidative
coupling
reaction
with
alcohols
that
proceeds
through
synergistic
deprotonation,
halogenation
and
substitution
sequence.
The
combination
of
tert-butoxide
bases
2-halothiophene
halogen
oxidants
enables
the
first
general
protocol
for
generating
using
benzyl
halides
deprotonative
pathway.
In
contrast
to
existing
radical-based
pathways
functionalization,
this
process
is
guided
by
acidity
trends.
This
gives
rise
new
synthetic
capabilities,
including
ability
functionalize
diverse
methyl(hetero)arenes,
tolerance
oxidizable
nucleophilic
functional
groups,
precision
regioselectivity
polyalkylarenes
use
double
etherification
controllably
oxidize
methylarenes
benzaldehydes.
Asian Journal of Organic Chemistry,
Год журнала:
2024,
Номер
13(4)
Опубликована: Фев. 8, 2024
Abstract
We
report
a
metal‐free
method
for
benzylic
C(sp
3
)−H
alkoxylation
with
silyl
ether
as
an
alkoxylating
agent.
The
reaction
is
considered
to
proceed
through
sequence
consisting
of
hydrogen
atom
transfer
(HAT)
and
oxidative
radical‐polar
crossover,
wherein
Selectfluor
serves
one‐electron
oxidant,
HAT
agent,
fluoride
ion
source.
formed
in
situ
activates
the
give
alkoxide
nucleophile,
which
reacts
benzyl
cation
intermediate
provide
product.
present
protocol
has
broad
substrate
scope,
enabling
C−H
primary,
secondary,
tertiary
bonds.
Furthermore,
it
applicable
late‐stage
bioactive
molecules.
