Radical Brook rearrangement: past, present, and future
Chemical Society Reviews,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 1, 2025
This
review
aims
to
provide
an
overview
of
radical
Brook
rearrangement,
which
is
organized
by
grouping
three
type
reactive
species
generated
via
the
unique
rearrangement
process.
Language: Английский
Asymmetric Trapping of Siloxyketenes In Situ Generated from [1,3]-Silyl Migration of α-Ketoacylsilanes: A Visible-Light-Driven Palladium-Catalyzed [4 + 2] Cycloaddition
ACS Catalysis,
Journal Year:
2025,
Volume and Issue:
unknown, P. 5796 - 5805
Published: March 25, 2025
The
transition
metal-catalyzed
asymmetric
[n
+
2]
cycloaddition
reaction
with
oxy-substituted
ketene
intermediates
remains
a
synthetic
challenge
due
to
the
limited
availability
of
suitable
precursors.
Herein,
we
report
visible-light-driven,
palladium-catalyzed
[4
vinyl
benzoxazinanones
siloxyketene
intermediates,
generating
structurally
diverse
chiral
quinolinone
derivatives
satisfactory
diastereo-
and
enantioselectivities.
transient
generation
siloxyketenes
from
α-ketoacylsilylanes
through
visible-light-induced
Brook
rearrangement
is
important
for
success
present
cycloaddition.
13C-labeling
experiments
reveal
pathway
involving
[1,3]-silyl
migration
process.
side
arm
effects
BOX
ligand
silyl
steric
hindrance
α-ketoacylsilanes
play
crucial
roles
in
stereoselectivity
control,
theoretical
calculations
provide
insights
into
stereochemical
outcome
reaction.
Language: Английский
Fluoroalkylacylsilanes as Novel Ambiphilic Donor–Acceptor Carbene Precursors
Accounts of Chemical Research,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 25, 2025
ConspectusCarbenes,
as
highly
reactive
intermediates,
have
emerged
pivotal
tools
in
organic
synthesis,
catalysis,
and
materials
science
due
to
their
versatile
reactivity
broad
applicability.
Among
the
diverse
classes
of
carbenes,
donor-acceptor
carbenes
(DACs)
attracted
significant
attention
owing
unique
electronic
properties
exceptional
reaction
selectivity.
The
distinctive
DACs
arises
from
synergistic
interplay
between
electron-withdrawing
electron-donating
groups
attached
carbene
center,
enabling
a
wide
array
transformations.
These
attributes
established
indispensable
building
blocks
for
constructing
complex
molecular
architectures
achieving
precise
control
over
chemical
transformation.This
Account
highlights
our
recent
advancements
development
fluoroalkylacylsilanes
novel
precursors
DACs.
Under
photocatalytic
conditions,
these
generate
fluoroalkyl
siloxycarbenes
via
radical
Brook
rearrangement.
group,
known
its
strong
properties,
imparts
electrophilic
characteristics,
while
siloxyl
group
stabilizes
center.
Together,
functionalities
render
ideal
candidates
generation
DACs,
providing
platform
range
transformations,
including
cycloadditions,
bond
insertions,
construction
new
structures.First,
we
developed
visible-light-induced,
organocatalyzed
[2
+
1]
cyclization
alkynes
trifluoroacetylsilanes,
leading
synthesis
cyclopropenols.
Mechanistic
studies
provided
compelling
evidence
involvement
triplet
intermediates
this
reaction,
demonstrating
utility
functionalized
cyclic
compounds.
Second,
explored
cyclopropanation
reactions
elucidated
diastereoselective
transfer
trifluoroacetylsilane-derived
alkenes.
Density
functional
theory
(DFT)
calculations
revealed
key
insights
into
origins
observed
diastereoselectivity,
offering
molecular-level
understanding
stereochemical
outcomes.
Additionally,
extended
scope
include
organoboronic
esters,
divergent
ketones.
By
modulating
situ-generated
organoboronate
complexes─formed
through
with
esters─we
achieved
selective
both
fluorine-maintaining
defluorinated
This
transition-metal-free
approach
is
operationally
simple
compatible
substrates,
aryl,
alkenyl,
alkyl
boronic
esters.
Beyond
C-B
functionalization,
applied
C(sp2)-H
functionalization
1,3-azoles.
investigations
suggest
that
success
stems
dual
role
trifluoroacetylsilanes
under
conditions:
they
not
only
participate
but
also
produce
biradicals
facilitate
ring-opening
aromatization
fused
cyclopropanes.We
anticipate
work
on
ambiphilic
will
lay
groundwork
further
use
acylsilanes
chemistry.
developments
are
expected
inspire
strategies
design
expand
silanes
synthetic
opening
avenues
intricate
architectures.
Language: Английский
Visible-Light-Induced [2 + 2] Cyclization of Alkynes with Bromodifluoroacetylsilanes: Facile Access to gem-Difluorocyclobutenones
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
147(19), P. 15955 - 15962
Published: April 29, 2025
Herein,
we
report
a
simple
and
efficient
method
for
the
synthesis
of
gem-difluorocyclobutenones
from
alkynes
bromodifluoroacetylsilanes,
proceeding
via
formal
cyclization
with
in
situ
generated
difluoroketene
under
visible-light-induced
conditions.
The
reaction
conditions
are
mild
exhibit
broad
substrate
scope,
including
both
aromatic
aliphatic
alkynes.
Additionally,
demonstrates
good
functional
group
tolerance,
facile
scalability,
potential
diverse
downstream
transformations.
Mechanistic
studies
suggest
that
bromodifluoroacetylsilanes
act
as
photochemical
precursors
to
difluoroketene.
Language: Английский
Recent Advances in Metal-Catalyzed Transformations of Acylsilanes via the Activation of C–Si Bonds
ACS Catalysis,
Journal Year:
2025,
Volume and Issue:
unknown, P. 8706 - 8723
Published: May 8, 2025
Language: Английский
Benzocyclobutenone Synthesis Exploiting Acylsilanes as Photofunctional Directing Groups
Chemical Science,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Jan. 1, 2024
The
visible-light
irradiation
of
acylsilane
tethered
vinyl
ketones
promotes
an
intramolecular
Stetter-type
reaction
Language: Английский