Chemistry Letters,
Journal Year:
2024,
Volume and Issue:
53(4)
Published: March 29, 2024
Abstract
In
this
study,
we
report
a
mechanochemical
protocol
for
highly
efficient
and
air-tolerant
calcium-based
Birch
reduction.
The
developed
approach
allows
the
use
of
readily
available
calcium
metal
as
safer-to-handle
reductant
reduction
various
aromatic
compounds.
reaction
was
rapid
desired
dearomatization
products
were
obtained
in
good
yields
within
15
min
at
ambient
temperature.
Notably,
all
synthetic
operations
can
be
performed
under
conditions
without
complicated
setup
involving
inert
gases.
feasibility
gram-scale
synthesis
demonstrated,
further
highlighting
practical
utility
protocol.
One
approach
to
mitigate
the
crisis
of
plastic
waste
is
“chemical
upcycling”,
in
which
converted
into
products
with
higher
economic
value.
Towards
this
goal,
several
metal-catalyzed
post-functionalization
polymers
have
been
reported,
variable
success,
mostly
on
account
lack
selectivity,
use
harsh
reaction
conditions,
and
environmentally
unfriendly
solvents.
In
work,
we
demonstrate
selective
hydroxylation
backbone
3°
C-H
bonds
polyolefin
macromolecules
using
in-house
developed
(Et4N)2[FeIII-(Ph,Me-bTAML)]
(3)
complex
solid
Na2CO3.1.5
H2O2
(SPC;
Sodium
percarbonate)
under
solvent-free
mechanochemical
conditions.
The
condition
only
employs
simple
grinding
at
room
tempera-ture.
polar
functional
group
-OH
was
successfully
incorporated
polymer
without
any
chain
degradation
crosslinking.
same
conditions
were
also
employed
selectively
hydroxylate
small
organic
molecules
including
com-plex
natural
products.
rate
selectivity
towards
far
exceed
that
performed
homogene-ous
Mechanistic
investigation
indicates
formation
well-characterized
oxoiron(V)
intermediate
upon
mechani-cal
3
SPC.
high
observed
due
elimination
solvent-induced
side-reaction
intermediate.
This
represents
a
very
sustainable
process
since
it
uses
benign
reagents
(iron
complex,
“oxygen
bleach”),
thus
eliminating
hazardous
workup
protocol
involves
washing
water
where
both
spent
catalyst
oxidant
are
soluble.
Advanced Synthesis & Catalysis,
Journal Year:
2024,
Volume and Issue:
366(7), P. 1509 - 1516
Published: Feb. 19, 2024
Abstract
The
reaction
of
chlorosilanes
with
organometallic
reagents
is
an
old
and
well‐developed
approach
to
organosilicon
compounds,
however,
its
application
was
limited
due
the
sensitivity
air,
water.
Here
we
display
a
mechanochemical
access
arylsilanes
via
Barbier‐type
aryl
halide
magnesium.
By
treatment
two
halides
Mg
powder
under
electromagnetic
milling,
series
are
obtained
within
15
minutes.
Taking
advantages
this
protocol
features
transition‐metal
free,
good
functional
group
tolerance,
air
stable
mild
conditions.
Chemistry Letters,
Journal Year:
2024,
Volume and Issue:
53(4)
Published: March 29, 2024
Abstract
Herein,
we
report
the
first
solid-state
protocol
for
nickel(0)-mediated
Yamamoto-coupling
reactions
using
ball
milling.
A
variety
of
aryl
halides
reacted
efficiently
in
presence
bis(cyclooctadiene)nickel(0)
[Ni(cod)2]
and
4,4'-di-tert-butyl-2,2'-bipyridyl
under
mechanochemical
conditions,
affording
corresponding
biaryls
high
yields.
Considering
that
potentially
harmful
high-boiling
organic
solvents
are
not
required,
present
study
provides
a
more
convenient,
environmentally
friendly,
sustainable
alternative
to
conventional
solution-based
Yamamoto
coupling.
Solid-state
polymerization
development
catalytic
variant
also
described.
Chemistry Letters,
Journal Year:
2024,
Volume and Issue:
53(4)
Published: March 29, 2024
Abstract
In
this
study,
we
report
a
mechanochemical
protocol
for
highly
efficient
and
air-tolerant
calcium-based
Birch
reduction.
The
developed
approach
allows
the
use
of
readily
available
calcium
metal
as
safer-to-handle
reductant
reduction
various
aromatic
compounds.
reaction
was
rapid
desired
dearomatization
products
were
obtained
in
good
yields
within
15
min
at
ambient
temperature.
Notably,
all
synthetic
operations
can
be
performed
under
conditions
without
complicated
setup
involving
inert
gases.
feasibility
gram-scale
synthesis
demonstrated,
further
highlighting
practical
utility
protocol.
