Dalton Transactions,
Год журнала:
2024,
Номер
unknown
Опубликована: Янв. 1, 2024
Methyl
magnesium
bromide
is
a
precatalyst
for
the
dehydrocoupling
of
silanes
and
amines
to
produce
aminosilane
products
under
mild
conditions.
As
commercially
available
Grignard
reagent,
this
represents
simplification
over
previous
magnesium-containing
catalysts
Si-N
bond
formation
while
displaying
similar
activity
other
magnesium-based
catalysts.
This
observation
consistent
with
hypothesis
that
competitive
Schlenk
equilibrium
can
be
addressed
by
not
using
an
ancillary
ligand.
While
MeMgBr
lower
than
some
reported
catalysts,
including
precatalysts,
unique
selectivity
was
observed
may
allow
directed
synthesis
products.
work
continues
increase
accessibility
heterodehydrocoupling
through
growing
family
precatalysts
balance
selectivity.
Advanced Synthesis & Catalysis,
Год журнала:
2024,
Номер
366(11), С. 2382 - 2431
Опубликована: Апрель 12, 2024
Abstract
This
contribution
offers
a
comprehensive
overview
of
methods
for
forging
sp
C−Si
bonds.
Over
time,
alkynylsilanes
(silylacetylenes),
once
considered
mere
byproducts
hydrosilylation
processes,
have
become
essential
building
blocks
in
organic
synthesis.
literature
review
traces
the
evolution
their
synthesis,
from
traditional
methodologies
relying
on
organolithium
and
organomagnesium
compounds
to
more
advanced
cross‐coupling
reactions
involving
hydro‐
carbosilanes.
Focused
primarily
past
25
years
(2000–2024),
it
also
extensively
references
significant
historical
breakthroughs.
By
analyzing
synthetic
methodologies,
not
only
survey
current
state
knowledge
but
identifies
areas
improvement.
Furthermore,
emphasize
importance
1‐alkynylsilanes
(1‐silyl‐1‐alkynes),
selected
applications
these
are
highlighted,
confirming
potential
Organic Letters,
Год журнала:
2024,
Номер
26(10), С. 1991 - 1995
Опубликована: Март 1, 2024
A
carboxylate-catalyzed,
metal-free
C-silylation
protocol
for
terminal
alkynes
is
reported
using
a
quaternary
ammonium
pivalate
as
the
catalyst
and
commercially
available
N,O-bis(silyl)acetamides
silylating
agents.
The
reaction
proceeds
under
mild
conditions,
tolerates
range
of
functionalities,
enables
concomitant
O-
or
N-silylation
acidic
OH
NH
groups.
Hammett
ρ
value
+1.4
±
0.1
obtained
para-substituted
2-arylalkynes
consistent
with
proposed
catalytic
cycle
involving
turnover-determining
deprotonation
step.
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(20), С. 4237 - 4244
Опубликована: Янв. 1, 2023
An
N-heterocyclic
carbene-zinc
alkyl
complex
[ImDippZn(CH2CH3)2]
(Im
=
imidazol-2-ylidene
and
Dipp
2,6-diisopropylphenyl)
acts
as
a
catalyst
in
the
cross-dehydrogenative
coupling
(CDC)
of
wide
range
primary
secondary
amines
hydrosilanes
to
yield
substantial
quantity
corresponding
aminosilanes
with
good
chemoselectivity
at
room
temperature.
A
broad
substrate
scope
was
observed
during
zinc-catalyzed
CDC
reaction.
Two
zinc
complexes,
[{ImMesZn(μ-NHPh)(NHPh)}2]
(Mes
mesityl)
(3)
[{ImDippZn(CH2CH3)(μ-H)}2]
(4),
were
isolated
structurally
characterized
intermediates
through
controlled
reactions
ascertain
mechanism.
Abstract
Cobalt
complexes
featuring
triazine‐based
PNP
ligands
have
proven
to
be
exceptionally
active
and
chemoselective
pre‐catalysts
in
facilitating
the
dehydrogenative
coupling
between
silanes
amines,
leading
synthesis
of
diverse
aminosilanes.
Notably,
even
challenging
substrates
exhibited
high
reactivity.
The
catalyst‘s
unique
feature
avoiding
with
tertiary
enhances
process
chemoselectivity.
It
facilitates
a
more
precise
silylamines
possessing
SiH
2
−N
SiH−N
motifs,
overcoming
challenges
associated
broader
reactivity
seen
previous
systems.
In
terms
its
remarkable
chemoselectivity,
it
is
also
noteworthy
that
catalytic
system
exhibits
both
versatility
efficacy
converting
untouched
double
triple
carbon‐carbon
bonds.
This
accomplishment
particularly
significant,
given
brought
about
by
activity
commonly
employed
catalysts
competitive
hydrosilylation
process.
ACS Sustainable Chemistry & Engineering,
Год журнала:
2023,
Номер
11(30), С. 11172 - 11180
Опубликована: Июль 17, 2023
The
phosphine-substituted
aryl
diimine
cobalt
catalyst,
(Ph2PPrADI)Co,
has
been
found
to
mediate
the
dehydrocoupling
of
diamines
or
polyamines
poly(methylhydrosiloxane)
(PMHS)
generate
hydrogen
and
crosslinked
solids
in
an
atom-efficient
fashion.
resulting
siloxane
diamine
polyamine
networks
persist
presence
air
water
at
room
temperature
can
tolerate
temperatures
up
1600
°C.
Upon
lowering
catalyst
loading
0.01
mol
%,
(Ph2PPrADI)Co
was
catalyze
1,3-propanediamine
PMHS
(m
=
35)
a
foam
with
turnover
frequency
157
s–1
relative
consumption,
highest
activity
ever
reported
for
Si–N
dehydrocoupling.
Furthermore,
upon
systematically
reducing
number
potential
branch
points,
(Ph2PPrADI)Co-catalyzed
hydride-terminated
poly(dimethylsiloxane)
(PDMS)
yield
linear
polymers
molecular
weights
47,300
g/mol.
Green Chemistry,
Год журнала:
2024,
Номер
26(9), С. 5284 - 5292
Опубликована: Янв. 1, 2024
Turnover
frequencies
of
up
to
300
s
−1
have
been
achieved
for
the
Mn-based
dehydrocoupling
silanes
and
diamines
yield
crosslinked
networks
that
absorb
organic
solvents
afford
coatings.
Inorganic Chemistry,
Год журнала:
2024,
Номер
64(1), С. 255 - 267
Опубликована: Дек. 23, 2024
An
active
catalytic
system
for
the
cross-dehydrogenative
coupling
(CDC)
of
a
wide
range
secondary
amines
with
silanes
is
reported.
The
iridium(III)
derivatives
[Ir(H)(X)(κ2-NSiDMQ)(L)]
(NSiDMQ
=
{4,8-dimethylquinoline-2-yloxy}dimethylsilyl;
L
coe,
X
Cl,
2;
OTf,
3;
PCy3,
4;
5),
which
are
stabilized
by
weak
yet
noticeable
Ir···H–C
agostic
interaction
between
iridium
and
one
C–H
bonds
8-Me
substituent
NSiDMQ
ligand,
have
been
prepared
fully
characterized.
These
species
proven
to
be
effective
catalysts
CDC
hydrosilanes.
best
performance
(TOF1/2
79,300
h–1)
was
obtained
using
5
(0.25
mol
%),
N-methylaniline,
HSiMe2Ph.
activity
[Ir(H)(OTf)(κ2-NSiQ)(PCy3)]
(10,
NSiQ
{quinoline-2-yloxy}dimethylsilyl)
[Ir(H)(OTf)(κ2-NSiMQ)(PCy3)]
(11,
NSiMQ
{4-methylquinoline-2-yloxy}dimethylsilyl),
related
but
lacking
substituent,
markedly
lower
than
that
found
5.
This
fact
highlights
crucial
role
ligand
in
enhancing
these
complexes.
