This
chapter
focuses
on
the
catalytic
activation
of
Si─H
bonds
by
boron
Lewis
acid
tris(pentafluorophenyl)borane
(BCF).
It
begins
with
a
general
overview
silanes
and
is
followed
discussion
characteristics
bond
mechanism
for
its
BCF-type
catalysts
(via
η1-[B]–H–[Si]
adduct).
Four
different
classes
BCF-catalyzed
reductions
involving
are
articulated,
organized
around
polarity
type
(σ
or
π)
being
reduced.
These
examples
provide
comprehensive
acid-catalyzed
reactions
silanes.
treatise
concludes
comparison
select
other
main-group
that
activate
Journal of the American Chemical Society,
Journal Year:
2021,
Volume and Issue:
143(48), P. 20002 - 20014
Published: Nov. 17, 2021
The
articulation
of
the
notion
"frustrated
Lewis
pairs"
(FLPs)
emerged
from
discovery
that
H2
can
be
reversibly
activated
by
combinations
sterically
encumbered
main
group
acids
and
bases.
This
has
prompted
numerous
studies
focused
on
various
perturbations
acid/base
applications
to
organic
reductions.
Perspective
focuses
new
directions
developments
are
emerging
this
FLP
chemistry
involving
hydrogen.
Three
areas
discussed
including
approaches
reductions,
reductions
small
molecules,
advances
in
heterogeneous
systems.
These
foci
serve
illustrate
despite
having
its
roots
chemistry,
simple
concept
FLPs
is
being
applied
across
discipline.
Chemistry - A European Journal,
Journal Year:
2023,
Volume and Issue:
29(32)
Published: March 27, 2023
We
describe
an
operationally
simple
and
user-friendly
protocol
that
allows
the
site-selective
hydrogenation
deuteration
of
di-,
tri-
tetrasubstituted
benzylic
olefins
by
electroreduction
while
other
groups
prone
to
are
present.
The
radical
anionic
intermediates
react
with
most
inexpensive
hydrogen/deuterium
source
H2
O/D2
O.
Our
method
overcomes
many
limitations
arise
from
previously
reported
electroreductive
hydrogenations.
applicability
this
reaction
is
demonstrated
a
broad
substrate
scope
(>50
examples)
focuses
on
functional
group
tolerance
sites
affected
metal-catalyzed
(alkenes,
alkynes,
protecting
groups).
Organic Letters,
Journal Year:
2018,
Volume and Issue:
20(15), P. 4672 - 4676
Published: July 23, 2018
A
catalytic,
metal-free
O–H
bond
insertion
of
α-diazoesters
in
water
the
presence
B(C6F5)3·nH2O
(2
mol
%)
was
developed,
affording
a
series
α-hydroxyesters
good
to
excellent
yields.
The
reaction
features
easy
operation
and
wide
substrate
scope,
importantly,
no
metal
is
needed
as
compared
with
conventional
methods.
Significantly,
this
approach
further
expands
applications
B(C6F5)3
under
water-tolerant
conditions.
Chemical Communications,
Journal Year:
2018,
Volume and Issue:
55(9), P. 1217 - 1220
Published: Dec. 21, 2018
A
transition
metal-free
intermolecular
redox-neutral
β-alkylation
of
acyclic
tertiary
amines
via
borrowing
hydrogen
catalyzed
by
commercially
available
B(C6F5)3
was
achieved.
Angewandte Chemie International Edition,
Journal Year:
2019,
Volume and Issue:
59(7), P. 2715 - 2719
Published: Dec. 6, 2019
Abstract
Molecular
compounds
featuring
nitrogen
atoms
are
typically
regarded
as
Lewis
bases
and
extensively
employed
donor
ligands
in
coordination
chemistry
or
nucleophiles
organic
chemistry.
By
contrast,
electrophilic
nitrogen‐containing
much
rarer.
Nitrenium
cations
a
new
family
of
nitrogen‐based
acids,
the
reactivity
which
remains
largely
unexplored.
In
this
work,
nitrenium
ions
explored
catalysts
five
transformations.
These
reactions
first
examples
acid
catalysis
employing
site
substrate
activation.
Moreover,
these
readily
accessed
from
commercially
available
reagents
exhibit
remarkable
stability
toward
moisture,
allowing
for
benchtop
transformations
without
need
to
pretreat
solvents.
Journal of the American Chemical Society,
Journal Year:
2018,
Volume and Issue:
141(2), P. 1135 - 1140
Published: Dec. 14, 2018
The
design
and
a
gram-scale
synthesis
of
bench-stable
cyclohexa-1,4-diene-based
surrogate
gaseous
hydrogen
iodide
are
described.
By
initiation
with
moderately
strong
Brønsted
acid,
is
transferred
from
the
onto
C–C
multiple
bonds
such
as
alkynes
allenes
without
involvement
free
iodide.
fragments
into
toluene
ethylene,
easy-to-remove
volatile
waste.
This
hydroiodination
reaction
avoids
precarious
handling
or
hydroiodic
acid.
this,
broad
range
previously
unknown
difficult-to-prepare
vinyl
iodides
can
be
accessed
in
stereocontrolled
fashion.
Angewandte Chemie International Edition,
Journal Year:
2018,
Volume and Issue:
57(38), P. 12356 - 12359
Published: Aug. 14, 2018
Abstract
Herein
we
report
the
first
catalytic
transfer
hydrogenation
of
silyl
enol
ethers.
This
metal
free
approach
employs
tris(pentafluorophenyl)borane
and
2,2,6,6‐tetramethylpiperidine
(TMP)
as
a
commercially
available
FLP
catalyst
system
naturally
occurring
γ‐terpinene
dihydrogen
surrogate.
A
variety
ethers
undergo
efficient
hydrogenation,
with
reduced
products
isolated
in
excellent
yields
(29
examples,
82
%
average
yield).
Organic Letters,
Journal Year:
2020,
Volume and Issue:
22(20), P. 7797 - 7803
Published: Sept. 29, 2020
We
report
herein
a
B(C6F5)3-catalyzed
redox-neutral
β-functionalization
of
pyrrolidines
with
isatins.
Under
transition-metal-
and
oxidant-free
conditions
at
ambient
temperature,
series
bearing
functionalized
exocyclic
alkene
are
accessed
in
high
efficiency
through
borrowing
hydrogen
process.
A
simple
switch
to
higher
reaction
temperature
one-pot
procedure
also
provides
access
diverse
array
C(3)-functionalized
pyrroles
while
liberating
water
gas
as
the
only
byproducts.
The Journal of Organic Chemistry,
Journal Year:
2019,
Volume and Issue:
84(7), P. 4478 - 4485
Published: March 11, 2019
A
challenging
metal-free
azide
insertion
of
α-aryl
α-diazoesters
in
the
presence
B(C6F5)3
(5
mol
%)
was
developed
for
first
time.
The
reaction
features
an
easy
operation,
wide
substrate
scope,
and
mild
conditions
affords
corresponding
products
moderate
to
high
yields.
More
importantly,
alkene
alkyne
functional
groups
were
well
tolerated
because
no
cyclopropanation
or
cyclopropenation
observed.
Furthermore,
could
be
converted
primary
amines
1,2,3-triazole
derivatives
after
simple
transformations.
