Research Square (Research Square),
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 24, 2024
Abstract
Although
the
directing
group
assisted
ortho-B
−
H
activation
reactions
of
o-carboranes
have
been
well
established
during
past
decade,
meta-B
are
unexplored
so
far.
Herein,
iridium(III)-catalyzed
remote
B(9)
alkylation
with
nitrile
template
demonstrated
for
first
time.
It
was
revealed
that
fine
tuning
structures
is
essential
high
reaction
efficiency
and
regioselectivity.
This
process
exhibits
a
broad
substrate
scope
good
functional
tolerance
under
simple
conditions.
The
template,
readily
accessible
from
o-carborane
acids,
can
be
removed
conveniently
after
completion
reaction.
present
method
provides
powerful
synthetic
route
to
complex
derivatives,
demonstrating
successful
larger
scale
further
molecular
transformations
B(9)-alkylated
products.
Organic Letters,
Год журнала:
2023,
Номер
25(25), С. 4621 - 4626
Опубликована: Июнь 15, 2023
We
present
here
an
iridium-catalyzed
diastereo-
and
enantioselective
[4
+
1]
cycloaddition
reaction
of
hydroxyallyl
anilines
with
sulfoxonium
ylides
under
mild
conditions,
leading
to
3-vinyl
indolines
in
moderate
good
yields
excellent
enantioselectivities.
Control
experiments
disclosed
a
plausible
mechanism.
Advanced Synthesis & Catalysis,
Год журнала:
2022,
Номер
364(24), С. 4174 - 4188
Опубликована: Дек. 1, 2022
Abstract
Carboranes,
a
three‐dimensional
class
of
carbon‐boron
molecular
clusters
with
remarkable
electronic,
physical,
chemical
characteristics,
have
proved
as
useful
building
blocks
in
boron
neutron
capture
therapy
agents,
supramolecular
design,
optoelectronics,
nanomaterials
and
organometallic/coordination
chemistry.
Thus,
various
organic
modifications
the
B−H
C−H
functionalities
carboranes
been
developed.
These
methods
great
success
utilize
directing
groups,
such
carboxylic
acids,
to
achieve
selective
functionalization
carboranes.
The
carboxyl
group
can
be
easily
introduced
then
removed
after
reactions.
On
other
hand,
assisted
by
highly
regioselective
electrophilic
attack
at
electron‐rich
positions
B(4)
B(5)
cage
generates
five‐membered
metallacyclic
intermediates,
which
undergo
further
transformation.
In
this
review,
we
show
that
transition
metal‐catalyzed
decarboxylation
cross
coupling
reactions
offer
an
opportunity
for
direct
activation
magnified
image
Abstract
Carboranes
are
a
type
of
molecular
clusters
consisting
carbon,
hydrogen,
and
boron
atoms.
They
possess
unique
characteristics,
such
as
three-dimensional
aromaticity,
icosahedral
geometry,
robustness.
Functionalized
carboranes
have
been
utilized
in
various
fields,
including
medicine,
materials,
organometallic/coordination
chemistry.
In
this
context,
selective
functionalization
o-carboranes
has
received
tremendous
attention,
specifically
the
regio-
enantioselective
modification
ten
chemically
similar
BH
vertices
within
carborane
cage.
recent
years,
significant
progress
made
catalytic
vertex-specific
functionalization,
well
achieving
cage
BH.
This
review
provides
an
overview
advancements
research
field.
1
Introduction
2
Carboxy-Assisted
Functionalization
2.1
Formation
B–C
Bonds
2.2
B–N
2.3
B–O
2.4
B–X
2.5
Consecutive
B–Y
(Y
=
N,
O)
3
N-Based
Directing-Group-Assisted
B–H
3.1
Acylamino
Directing
Group
3.2
Amide
3.3
Pyridyl
3.4
Imine
4
Phosphinyl-Assisted
Cage
5
Bidentate-Directing-Group-Assisted
6
Other
7
Conclusions
Chemical Science,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 1, 2025
Despite
significant
progress
in
the
B-H
functionalization
of
carboranes,
development
cost-effective
catalytic
systems
devoid
noble
metals,
coupled
with
mechanistic
validation
regioselectivity
control,
remains
a
formidable
challenge.
Herein,
we
disclose
an
Ag
salt-free,
redox-neutral,
and
inexpensive
ruthenium(ii)-catalyzed
protocol
that
enables
exclusive
B(4)-H
acylmethylation
o-carboranes
through
novel
post-coordination
strategy.
By
exploiting
weakly
coordinating
carboxylic
acid
as
traceless
directing
group,
this
method
achieves
excellent
mono-site
selectivity
for
B-C(sp3)
bond
formation
using
diverse
sulfoxonium
ylides,
demonstrating
both
functional
group
tolerance
synthetic
scalability.
This
work
not
only
establishes
practical
platform
but
also
addresses
critical
questions
unresolved
prior
analogous
studies.
Through
deuterium
labeling,
situ
high-resolution
mass
spectrometry
(HRMS)
tracking,
single-crystal
X-ray
analysis
Ru
intermediates,
unequivocally
demonstrate
originates
from
unique
mode
Ru(ii).
The
catalyst
simultaneously
engages
enolizable
acylmethyl
moiety
mono-acylated
intermediate,
thereby
dictating
activation
trajectory.
Our
findings
establish
generalizable
regiocontrolled
carborane
while
defining
paradigms
transition
metal-mediated
chemistry.
Inorganic Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 21, 2025
A
transition-metal-catalyzed
iterative
multiple
cage
B-H
activation
reaction
for
constructing
multifunctionalization
of
o-carboranes
in
one
pot
is
challenging.
Herein,
palladium-catalyzed
regioselective
tetra-arylation
a
wide
range
C(1)-N-aryl-o-carboranyl
amides
with
aryl
iodides
has
been
developed.
variety
B(3,4,5,6)-tetra-arylated
were
synthesized
good-to-excellent
yields.
Moreover,
the
mono-,
di-,
and
triarylated
intermediate
products
isolated,
exact
structures
determined
by
NMR,
high-resolution
mass
spectrometry,
X-ray
analysis,
which
provide
rationale
that
order
introduction
groups
into
o-carborane
B(4)
>
B(5)
B(3)/B(6).
This
protocol
represents
powerful
synthetic
method
polyfunctionalization
derivatives
under
very
mild
simple
conditions,
offers
valuable
reference
design
synthesis
molecular
propellers
based
on
carboranes.
Organic Letters,
Год журнала:
2022,
Номер
24(17), С. 3128 - 3133
Опубликована: Апрель 25, 2022
We
disclose
an
iridium(III)-catalyzed
regioselective
B(4)-H
allenylation
of
o-carboranes
from
o-carborane
acids
and
propargyl
carbonates
under
ball-milling
conditions.
This
study
sheds
light
on
a
novel
method
to
accomplish
B(4)-allenylation
that
cannot
be
realized
through
conventional
solution-based
reactions.
Control
experiments,
including
solution,
neat,
microwave,
high-temperature
reactions,
reveal
the
is
unique
for
Organic Letters,
Год журнала:
2022,
Номер
24(39), С. 7077 - 7081
Опубликована: Сен. 23, 2022
We
report
here
a
catalytic
selective
cage
B4-H
amination
of
o-carboranes
employing
an
Ir(III)
complex
as
catalyst
and
anthranils
aminating
agents,
leading
to
large
class
B4-aminated
with
very
high
yields
broad
substrate
scope
under
mild
conditions
without
any
oxidants.
In
these
reactions,
the
carboxyl
group
serves
traceless
directing
unit
determine
site
selectivity
degree
substitution.
Organic Letters,
Год журнала:
2023,
Номер
25(36), С. 6643 - 6648
Опубликована: Авг. 30, 2023
Iridium(I)-catalyzed
regioselective
B(4)-alkenylation
has
been
developed
from
o-carboranyl
sulfoxonium
ylides
and
alkynes
through
B(4)–H
activation.
The
sequential
B(4)-
B(6)-alkenylation
afforded
B(3,5)-dialkenylated
in
one
pot.
Eventually,
two
alkenyl
groups,
the
same
or
different,
were
introduced
at
positions
3
5
of
carborane.
Sulfoxonium
ylide
used
as
a
directing
group
remains
available
for
further
functionalization
is
converted
to
B-alkenylated
trichloromethyl
ketones.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(10), С. 6974 - 6986
Опубликована: Май 4, 2024
A
LiBr-promoted
formal
C(sp3)–H
bond
insertion
reaction
between
β-carbonyl
esters
and
sulfoxonium
ylides
is
established.
This
practical
has
a
wide
range
of
substrate
scope
for
both
to
give
variety
1,4-dicarbonyl
compounds
with
43–94%
yields.
The
features
transition-metal-free
conditions
exclusive
C-alkylation
chemselectivity.
use
bench-stable
overcomes
previous
methods
that
require
transition
metal
as
catalysts
unstable
diazo
or
toxic
haloketones
alkylation
reagents.
