Journal of Physical Organic Chemistry,
Год журнала:
2022,
Номер
36(2)
Опубликована: Сен. 7, 2022
Abstract
Functionalization
at
target
site
is
an
extremely
challenging
subject
for
surface
modification
of
o
‐carborane.
It
a
common
tactic
to
introduce
directing
group
onto
the
C(2)–H
vertex
induce
exclusive
B(4,5)–H
functionalizations.
In
this
study,
was
investigated.
The
computational
results
indicate
that
formal
[4
+
2]
annulation
going
via
reductive
elimination
mechanism
has
kinetic
priority
than
alkenylation
decarboxylation
mechanism.
This
in
excellent
agreement
with
experimental
carborano‐isocoumarin
as
major
product.
Given
alkyne
insertion
product,
protonation
alkene
likely
occur
before
followed
by
carborane.
HOPiv
regioselectivity
determining
step,
and
non‐covalent
interaction
analysis
discloses
it
steric
repulsion
methyl
on
C(1)
atom
carborane
towards
iridacycle
Cp
*
causes
higher
barrier
B(3)–H
activation,
which
finally
leads
specific
B(4)–H
functionalization.
Organic Chemistry Frontiers,
Год журнала:
2023,
Номер
10(5), С. 1153 - 1159
Опубликована: Янв. 1, 2023
By
combining
HTE
and
machine
learning
technologies,
an
iridium(
i
)-catalyzed
highly
selective
O–H
bond
insertion
reaction
of
carboxylic
acids
sulfoxonium
ylides
was
developed,
extensive
space
exploration
accomplished.
Organic Letters,
Год журнала:
2022,
Номер
24(8), С. 1604 - 1609
Опубликована: Фев. 17, 2022
An
iridium(III)-catalyzed
regioselective
acylmethylation
of
the
cage
B(4)-H
bond
in
o-carborane
acids
with
sulfoxonium
ylides
is
demonstrated
through
activation
ethanol
under
very
mild
conditions,
affording
a
number
B(4)-acylmethylated
o-carboranes.
Additionally,
selective
sequential
B(4)-
and
B(6)-acylmethylation
reactions
finally
gave
B(3,5)-diacylmethylated
o-carboranes
one
pot.
Chemical Communications,
Год журнала:
2022,
Номер
58(89), С. 12443 - 12446
Опубликована: Янв. 1, 2022
Herein,
a
method
to
access
3-trifluoromethyl-1,4-benzoxazines
from
CF3-imidoyl
sulfoxonium
ylides
and
2-bromophenols
has
been
demonstrated.
This
synthetic
protocol
proceeds
via
one-pot
two-step
sequence
that
includes
the
lithium-bromide-promoted
O-H
insertion
of
annulation,
merits
broad
substrate
scope,
excellent
functional
tolerance
operational
simplicity,
which
provides
an
alternative
means
obtaining
CF3-substituted
heterocycles.
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.
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:
2022,
Номер
24(39), С. 7095 - 7100
Опубликована: Сен. 26, 2022
An
unprecedented
copper-catalyzed
cascade
reaction
of
1,6-enynes
with
sulfoxonium
ylides
is
reported,
providing
a
series
structurally
intriguing
2,3-disubstituted
indolines
bearing
conjugated
dienone
functionality
at
the
3-position
in
moderate
to
excellent
yields
good
chemo-,
regio-,
and
diastereoselectivities
under
mild
conditions.
Importantly,
sulfoxonium-ylide-derived
copper-carbene
herein
exhibits
quite
different
reactivity
from
that
diazo
copper-carbene.
A
rational
mechanism,
an
initial
ammonium
ylide
rather
than
allene
formation,
proposed.
