The Journal of Organic Chemistry,
Год журнала:
2022,
Номер
87(15), С. 9551 - 9564
Опубликована: Июль 11, 2022
An
atom
economic
method
demonstrates
the
involvement
of
noncovalent
interaction
via
hydrogen
or
halogen
bonding
in
triggering
paired
electrolysis
for
group
transfer
reactions.
Specifically,
this
demonstrated
bromination
several
aromatic
and
heteroaromatic
compounds
through
activation
C(sp3)-Br
bond
organic-bromo
derivatives
on
demand.
This
electrochemical
protocol
is
mild,
mostly
no
additional
electrolyte
needed,
which
makes
workup
process
straightforward.
Unlike
existing
regioselective
monobromination
methods,
work
utilizes
a
relatively
small
amount
(1.2
equiv)
bromine
surrogates
that
releases
demand
under
condition
after
completion
reaction
generates
acetophenone
as
useful
byproduct.
Green
metrics
indicate
has
very
good
efficiency
with
an
E-factor
26.86
kg
waste/1
product.
In
addition
to
scale-up
process,
strategy
could
be
extended
chlorine
thioaryl
units.
extensive
mechanistic
study
accomplished
validate
hypothesis
using
computational,
spectroscopic,
cyclic
voltammetry
studies.
Finally,
applicability
newly
developed
nonbonding
trigger
was
chemoselective
debromination
dihalo
organic
compounds.
European Journal of Organic Chemistry,
Год журнала:
2022,
Номер
2022(17)
Опубликована: Апрель 15, 2022
Abstract
An
environmentally
friendly
and
highly
efficient
electrochemical
method
has
been
developed
for
halogenation
of
2
H
‐indazoles
with
cheap
commercially
available
NaX
(X=Cl,
Br)
in
the
absence
metal
catalysts
oxidants.
Notably,
this
process
exhibits
a
broad
substrate
scope
high
functional‐group
compatibility.
A
variety
are
compatible
transformation
to
give
corresponding
products
modern
excellent
yields.
Also,
practical
protocol
avoids
using
external
expensive
supporting
electrolytes.
Last
but
not
least,
procedure
was
carried
out
an
undivided
cell
at
constant
current
condition
under
air
atmosphere.
An
efficient
electrochemical
bromocyclization
of
allenols
has
been
realized
for
the
synthesis
spirocyclic
2,5-dihydrofurans.
The
reaction
used
commercially
available
and
nontoxic
KBr
as
brominating
source
in
a
simple
setup
under
open-air
conditions.
Notably,
optically
active
products
can
be
obtained
from
2,3-allenols
without
any
racemization,
further
enhancing
synthetic
utility.
JACS Au,
Год журнала:
2022,
Номер
2(4), С. 793 - 800
Опубликована: Апрель 15, 2022
Hinckdentine
A,
a
marine-sponge-derived
tribrominated
indole
alkaloid
bearing
unique
indolo[1,2-c]quinazoline
skeleton,
was
completed
in
12
steps
featuring
the
construction
of
Nα-quaternary
carbon
center
by
asymmetric
azo-ene
cyclization.
A
novel
organocatalyst
developed
to
promote
high-yielding
tribromination,
which
represents
challenging
process
encountered
previous
syntheses.
Density
functional
theory
calculations
scrutinized
viable
substrates
and
deciphered
origin
enhancement
C8
electrophilic
bromination
with
bifunctional
organocatalyst.
Moreover,
application
organocatalyst-enabled
on
various
demonstrated
highlight
future
late
functionalizations
biologically
intriguing
targets.
Organic Letters,
Год журнала:
2022,
Номер
24(25), С. 4665 - 4669
Опубликована: Июнь 21, 2022
An
electrochemical
synthesis
of
diazo
compounds
from
hydrazones
in
yields
as
high
99%
was
performed.
This
method
elaborated
a
useful
synthetic
and
demonstrated
on
various
(24
examples).
Apart
exhibiting
an
efficiency
that
matched
commonly
used
harsh
toxic
chemical
oxidants,
this
reaction
is
practically
simple
to
set
up,
requires
mild
conditions,
highly
electron
efficient
(3
F/mol).
Chemistry - A European Journal,
Год журнала:
2023,
Номер
30(11)
Опубликована: Дек. 13, 2023
Abstract
We
report
a
rapid,
efficient,
and
scope‐extensive
approach
for
the
late‐stage
electrochemical
diselenation
of
BODIPYs.
Photophysical
analyses
reveal
red‐shifted
absorption
–
corroborated
by
TD‐DFT
DLPNO‐STEOM‐CCSD
computations
color‐tunable
emission
with
large
Stokes
shifts
in
selenium‐containing
derivatives
compared
to
their
precursors.
In
addition,
due
presence
heavy
Se
atoms,
competitive
ISC
generates
triplet
states
which
sensitize
1
O
2
display
phosphorescence
PMMA
films
at
RT
frozen
glass
matrix
77
K.
Importantly,
BODIPYs
demonstrate
ability
selectively
stain
lipid
droplets,
exhibiting
distinct
fluorescence
both
green
red
channels.
This
work
highlights
potential
electrochemistry
as
an
efficient
method
synthesizing
unique
emission‐tunable
fluorophores
broad‐ranging
applications
bioimaging
related
fields.
The Journal of Organic Chemistry,
Год журнала:
2021,
Номер
86(22), С. 16177 - 16186
Опубликована: Авг. 30, 2021
An
electrophotochemical
ring-opening
bromination
of
unstrained
tert-cycloalkanols
has
been
developed.
This
method
enables
the
oxidative
transformation
cycloalkanols
with
5-
to
7-membered
rings
into
synthetically
useful
ω-bromoketones
without
use
chemical
oxidants
or
transition-metal
catalysts.
Alkoxy
radical
species
would
be
key
intermediates
in
present
transformation,
which
generate
through
homolysis
O–Br
bond
hypobromite
under
visible
light
irradiation.
Sustainable Chemistry,
Год журнала:
2022,
Номер
3(4), С. 430 - 454
Опубликована: Окт. 13, 2022
The
electrochemical
generation
of
highly
reactive
and
hazardous
bromine
under
controlled
conditions
as
well
the
reduction
surplus
oxidizers
reagent
waste
has
placed
synthesis
in
a
highlighted
position.
In
particular,
dibromination
bromofunctionalization
alkenes
alkynes
have
received
significant
attention,
forming
synthetically
important
derivatives
can
be
generated
from
bench-stable
safe
bromide
sources
“green”
conditions.
Readily
available
non-corrosive
salts
been
utilized
with
dual
role
both
supporting
electrolyte.
However,
this
trend
seems
to
change
preparation
organobromine
species.
review,
was
addressed
terms
their
sustainability.
ACS Omega,
Год журнала:
2023,
Номер
8(26), С. 23851 - 23859
Опубликована: Июнь 22, 2023
A
one-pot
methodology
has
been
developed
to
synthesize
3-halo-pyrazolo[1,5-a]pyrimidine
derivatives
through
the
three-component
reaction
of
amino
pyrazoles,
enaminones
(or
chalcone),
and
sodium
halides.
The
use
easily
accessible
1,3-biselectrophilic
reagents
like
chalcone
offers
a
straightforward
approach
for
synthesis
3-halo-pyrazolo[1,5-a]pyrimidines.
proceeded
cyclocondensation
between
pyrazoles
with
enaminones/chalcone
in
presence
K2S2O8
followed
by
oxidative
halogenations
NaX-K2S2O8.
Mild
environmentally
benign
conditions,
wide
functional
group
tolerance,
scalability
are
attractive
facet
this
protocol.
combination
NaX-K2S2O8
is
also
beneficial
direct
pyrazolo[1,5-a]pyrimidines
water.
Reactions,
Год журнала:
2022,
Номер
3(2), С. 233 - 253
Опубликована: Апрель 3, 2022
Among
halogenated
molecules,
those
containing
chlorine
atoms
are
fundamental
in
many
areas
such
as
pharmaceuticals,
polymers,
agrochemicals
and
natural
metabolites.
Despite
the
fact
that
reactions
have
been
developed
to
install
on
organic
most
of
them
rely
toxic
hazardous
chlorinating
reagents
well
harsh
conditions.
In
an
attempt
move
towards
more
sustainable
approaches,
photoredox
catalysis
electrocatalysis
emerged
powerful
alternatives
traditional
methods.
this
review,
we
collect
recent
significant
examples
visible-light-
or
current-mediated
chlorination
published
last
five
years.
