Organic & Biomolecular Chemistry,
Год журнала:
2024,
Номер
22(12), С. 2324 - 2338
Опубликована: Янв. 1, 2024
This
review
summarizes
the
most
recent
progress
made
in
C–H
bond
activation-initiated
spiroannulation
reactions
and
their
applications
construction
of
structurally
diverse
biologically
valuable
spirocyclic
scaffolds.
Cascade
annulation
reactions
can
assemble
structurally
intricate
polycyclic
molecules
from
simple
starting
materials
with
enhanced
efficiency
and
minimized
production
of
waste.
Presented
herein
is
a
concise
effective
synthesis
benzoisochromene
derivatives
based
on
C-H
activation-initiated
cascade
formal
[4+2]/[2+4]
aryl
enaminone
vinyl-1,3-dioxolan-2-one.
In
constructing
the
six-membered
carbocycle,
acted
as
C4
synthon
while
vinyl-1,3-dioxolan-2-one
C2
synthon.
O-heterocycle,
other
hand,
former
latter
C3O1
To
our
knowledge,
this
first
simultaneous
construction
both
carbocycle
an
O-heterocycle
via
concurrent
C-H/C-N/C-O
bond
cleavage
C-C/C-C/C-O
formation.
general,
novel
protocol
features
use
readily
obtainable
substrates
broad
scope,
excellent
atom-
step-economy,
intriguing
reaction
pathway,
valuable
products.
Angewandte Chemie International Edition,
Год журнала:
2021,
Номер
61(1)
Опубликована: Окт. 22, 2021
Axially
chiral
open-chain
olefins
represent
an
underexplored
class
of
platform.
In
this
report,
two
classes
tetrasubstituted
axially
acyclic
have
been
accessed
in
excellent
enantioselectivity
and
regioselectivity
via
C-H
activation
(hetero)arenes
assisted
by
a
migratable
directing
group
en
route
to
coupling
with
sterically
hindered
alkynes.
The
indoles
bearing
N-aminocarbonyl
afforded
C-N
acrylamides
the
assistance
racemic
zinc
carboxylate
additive.
DFT
studies
suggest
β-nitrogen
elimination-reinsertion
pathway
for
migration.
Meanwhile,
employment
N-phenoxycarboxamide
delivered
C-C
enamides
migration
oxidizing
group.
Experiments
that
both
cases
(hetero)arene
substrate
adopts
well-defined
orientation
during
activation,
which
turn
determines
disposition
alkyne
migratory
insertion.
Synthetic
applications
representative
are
demonstrated.
Chemical Communications,
Год журнала:
2021,
Номер
57(83), С. 10827 - 10841
Опубликована: Янв. 1, 2021
Over
the
last
decade,
high-valent
cobalt
catalysis
has
earned
a
place
in
spotlight
as
valuable
tool
for
C-H
activation
and
functionalization.
Since
discovery
of
its
unique
reactivity,
more
attention
been
directed
towards
utilization
an
alternative
to
noble
metal
catalysts.
In
particular,
Cp*Co(III)
complexes,
well
simple
Co(II)
Co(III)
salts
combination
with
bidentate
chelation
assistance,
have
extensively
used
development
novel
transformations.
this
review,
we
demonstrated
existing
trends
functionalization
methodology
using
highlighted
main
challenges
overcome,
perspective
directions,
which
need
be
further
developed
future.
Chemistry - An Asian Journal,
Год журнала:
2022,
Номер
17(15)
Опубликована: Июнь 6, 2022
Abstract
Transition‐metal‐catalyzed
tandem
reactions
have
become
a
mainstay
in
organic
chemistry
owing
to
their
high
atom‐
and
step‐economies.
Metal‐migration‐based
allow
the
engagement
of
simple
starting
materials
for
incorporating
functional
groups
into
certain
positions
constructing
complex
scaffolds,
which
provide
novel
means
that
are
complementary
traditional
cross‐coupling
or
C−H
activation
processes.
In
light
broad
utility
1,4‐Pd
migration
reaction,
this
paper
reviews
its
progress
past
two
decades,
summarizing
process
classifying
it
based
on
insertion,
elimination,
transmetalation,
bond
activation.
Special
emphasis
is
placed
driving
force
Pd
different
mechanisms.
Moreover,
review
also
attempts
summarize
common
strategies
improving
regio‐
site‐selectivities
process.
ACS Catalysis,
Год журнала:
2022,
Номер
12(4), С. 2330 - 2347
Опубликована: Фев. 1, 2022
Transition-metal-catalyzed
alkylation
of
(hetero)arenes
with
three-membered
carbo-/heterocycles
involving
C–H
activation
and
ring
scission
has
been
greatly
developed
over
the
past
few
years.
The
chelation-assisted
strategies
for
controlling
reactivity
site
selectivity
in
these
protocols
include
use
nitrogen-containing
directing
groups,
pre-existing
functional
a
Catellani-type
intermediate,
thereby
providing
rapid
access
to
numerous
oxygen-
or
heterocyclic
systems.
This
review
gives
an
update
area
various
catalytic
methodologies
applications
total
synthesis
natural
products
rings
as
alkylating
reagents,
which
are
classified
into
following
three
categories
on
basis
employed
strategies:
(i)
directed
by
(ii)
(iii)
aryl-NBE
intermediates
(Catellani-type
cascade
reaction).
Organic Letters,
Год журнала:
2023,
Номер
25(24), С. 4422 - 4428
Опубликована: Июнь 8, 2023
Presented
herein
is
a
condition-controlled
selective
synthesis
of
pyranone-tethered
indazoles
or
carbazole
derivatives
via
the
cascade
reactions
N-nitrosoanilines
with
iodonium
ylides.
Mechanistically,
formation
former
involves
an
unprecedented
process
including
nitroso
group-directed
C(sp2)–H
bond
alkylation
N-nitrosoaniline
ylide
followed
by
intramolecular
C-nucleophilic
addition
to
moiety,
solvent-assisted
cyclohexanedione
ring
opening,
and
transesterification/annulation.
On
contrary,
latter
initial
annulation
denitrosation.
These
developed
protocols
feature
easily
controllable
selectivity,
mild
reaction
conditions,
clean
sustainable
oxidant
(air),
valuable
products
that
are
structurally
diverse.
In
addition,
utility
was
showcased
their
facile
diverse
transformations
into
synthetically
biologically
interesting
compounds.
Organic Chemistry Frontiers,
Год журнала:
2024,
Номер
11(7), С. 1917 - 1923
Опубликована: Янв. 1, 2024
We
present
a
novel
synthesis
of
CF
3
-
and
alkynyl-substituted
quinoline
derivatives
based
on
Rh(
iii
)-catalyzed
cascade
reactions
N
-aryl
amidines
with
two
-ynones.
Then,
some
products
are
transformed
into
polycyclic
-benzo[
k
]phenanthridines
through
an
intramolecular
annulation
reaction.
