Handbook of CH‐Functionalization,
Год журнала:
2022,
Номер
unknown, С. 1 - 39
Опубликована: Окт. 2, 2022
Abstract
Rhodium
complexes
are
exceptionally
significant
in
homogeneous
catalysis.
The
synthetic
community
observed
the
rapid
burgeoning
of
such
rhodium
catalysis
since
discovery
Wilkinson's
catalyst.
Rhodium‐catalyzed
tandem
C(sp
2
)H/C(sp
3
)H
activation
and
annulation
with
alkenes,
alkynes,
arenes,
other
reactive
partners
is
a
rapidly
growing
research
field
to
obtain
new
class
heterocycles
thereby
generates
potential
biologically
active
pharmacophores.
Superior
reactivity
catalysts
attributed
due
its
good
π‐acceptor
character
that
favors
CH
bond
reaction
substrates
containing
wide
range
directing
groups,
as
amides,
imines,
carboxylic
acid
(derivatives),
benzylic
alcohols,
ketones,
various
shown
efficiency
toward
befitting
partners;
even
undirected
activations
have
also
been
achieved.
This
article
provides
brief
account
recent
developments
rhodium‐catalyzed
activation/annulation
reactions
for
synthesis
classes
fused
cyclic
scaffolds
using
suitable
coupling
partners.
For
strategies,
different
types
cyclization
reactions,
namely,
oxidative,
redox‐neutral,
photoredox,
electrochemical
discussed.
In
addition,
enantioselective
annulated
molecules
chiral
has
highlighted.
Advanced Synthesis & Catalysis,
Год журнала:
2023,
Номер
365(11), С. 1770 - 1776
Опубликована: Март 21, 2023
Abstract
Rh‐catalyzed
C−H
activation
of
arenes
for
oxidative
annulations
with
alkynes
stands
out
as
a
protocol
polycyclic
scaffolds.
This
perspective
drives
us
to
disclose
herein
rhodium
catalyzed
regioselective
triple
annulation
enaminones
hydroxyl‐alkynoates
via
double
functionalization
naphtho‐pyran
Secondary
coordination
OH
in
alkynoate
dictated
the
regioselectivity.
Initial
lactonization
occurred
chemoselectively
on
enamine
part
carbo
rhodation
followed
by
reductive
elimination.
was
scalable
and
has
shown
high
functionality
tolerance.
KIE
studies
were
done
get
insight
mechanism,
some
downstream
transformations
achieved
show
synthetic
potential
method.
Advanced Synthesis & Catalysis,
Год журнала:
2023,
Номер
365(18), С. 2991 - 3019
Опубликована: Июль 14, 2023
Abstract
Propargylic
alcohols
are
readily
available
bifunctional
(alkyne
and
hydroxyl
groups)
synthons,
which
recognize
as
one
of
the
attractive
synthetic
feedstock
in
organic
transformations.
Especially,
recent
years
employment
these
valuable
molecules
has
frequently
been
observed
literature.
Hence,
present
review
highlights
advancements
application
propargylic
cyclization,
substitution,
addition
reactions.
The Journal of Organic Chemistry,
Год журнала:
2021,
Номер
87(2), С. 1240 - 1248
Опубликована: Дек. 29, 2021
We
present
here
a
rhodium-catalyzed
oxidative
three-point
double
annulation
of
enaminones
with
propargylic
alcohols
via
C–H
and
C–N
bond
activation
to
access
arylnaphthalene-based
lignan
derivatives.
The
key
step
in
the
reaction
is
regioselective
insertion
alcohol
into
rhoda-cycle,
result
hydroxyl
rhodium
coordination.
Necessary
control
experiments
KIE
studies
were
conducted
determine
mechanism.
Angewandte Chemie International Edition,
Год журнала:
2022,
Номер
61(48)
Опубликована: Сен. 5, 2022
The
activation
of
carbon-hydrogen
bonds
is
considered
as
one
the
most
attractive
techniques
in
synthetic
organic
chemistry
because
it
bears
potential
to
shorten
routes
well
produce
complementary
product
scopes
compared
traditional
strategies.
However,
many
current
methods
employ
silver
salts
additives,
leading
stoichiometric
metal
waste
and
thereby
preventing
full
C-H
be
exploited.
Therefore,
development
silver-free
protocols
has
recently
received
increasing
attention.
Mechanistically,
can
serve
various
roles
thus,
avoiding
use
requires
different
approaches
based
on
role
serves
a
given
process.
In
this
Review,
we
present
comparison
silver-based
methods.
Focusing
strategic
develop
activation,
provide
reader
with
means
sustainable
for
activation.
Chemical Communications,
Год журнала:
2023,
Номер
59(64), С. 9714 - 9717
Опубликована: Янв. 1, 2023
A
Pd-catalyzed
rollover
cascade
dual
C–H
annulation
of
aryl
phenols
with
alkynols
for
producing
phenanthrene
scaffolds
in
a
regioselective
manner
was
developed.
Necessary
control,
KIE
and
deuterium
experiments
were
conducted
to
determine
the
reaction
mechanism.
Polycyclic aromatic compounds,
Год журнала:
2022,
Номер
43(4), С. 3099 - 3121
Опубликована: Апрель 7, 2022
4-(Dimethylamino)pyridine
(DMAP)
has
been
used
as
an
efficient
Brønsted
organo-base
catalyst
for
the
one-pot,
three-component
cyclization
of
various
aldehydes,
β-keto
esters,
and
hydroxylamine
hydrochloride.
In
this
organocatalyzed
reaction,
3,4-disubstituted
isoxazole-5(4H)-ones
were
efficiently
formed
in
high
yields
relatively
shorter
reaction
times.
Using
8
mol%
DMAP,
a
mixture
water–ethanol
solvent
system,
80
°C
gave
best
results.
The
heterocyclization
using
arylaldehydes
containing
electron
releasing
groups
is
well
performed
heterocyclic
products
obtained
good
to
isolated
yields.
Aldehydes
with
withdrawing
did
not
lead
formation
products.
This
method
many
advantages
such
broad
substituent
scope,
mild
eco‐friendly
conditions,
step
atom
economy,
commercially
available,
inexpensive
organo-basic
catalyst.
Organic & Biomolecular Chemistry,
Год журнала:
2022,
Номер
20(31), С. 6037 - 6056
Опубликована: Янв. 1, 2022
This
review
article
contains
various
synthetic
strategies
for
the
generation
of
pyridines,
quinolines,
and
isoquinolines
from
propargylic
alcohols
during
period
between
2005–2021.
is
first
focused
that
has
appeared
on
this
topic.
Organic Letters,
Год журнала:
2022,
Номер
24(28), С. 5062 - 5067
Опубликована: Июль 11, 2022
We
disclose
herein
a
Rh(III)-catalyzed
migratory
three-point
double
annulation
of
o-alkenyl
phenols
with
propargyl
alcohols
for
de
novo
construction
naphtho
furan
derivatives
in
regio-
and
chemoselective
manner.
The
protocol
orchestrates
two
new
rings
four
bonds
one
operation
without
the
need
any
additive.
Necessary
labeled
control
experiments
are
conducted
to
elucidate
reaction
mechanism.
A
tertiary
hydroxyl
group
is
found
be
crucial
both
controlling
regioselective
insertion
alkyne
through
chelation
rhodium
form
key
spiro
cyclic
intermediate
forcing
ring
expansion
via
unusual
selective
olefin
reshuffling,
apart
from
forming
an
extra
(furan)
ring.
scalable
shows
tolerance
late
stage
functionalization
natural
products.
The Journal of Organic Chemistry,
Год журнала:
2024,
Номер
89(6), С. 3834 - 3843
Опубликована: Фев. 29, 2024
Electrophilic
cyclization
and
concomitant
C–H
annulation
constitute
an
expedient
cascade
strategy
for
the
construction
of
multicyclic
scaffolds
with
precise
substitutional
patterns.
We
report
here
a
novel
Pd-catalyzed
cyclative
ynone
oxime
activated
alkynes.
The
features
dual
regioselectivity
including
site
selective
activation
chelation-assisted
insertion
Control
experiments
together
kinetic
give
insights
into
mechanism.
