Handbook of CH‐Functionalization,
Journal Year:
2022,
Volume and Issue:
unknown, P. 1 - 39
Published: Oct. 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.
Organic Letters,
Journal Year:
2022,
Volume and Issue:
24(16), P. 3014 - 3018
Published: April 14, 2022
1-Acryloyl-2-cyanoindoles
were
found
to
be
novel
and
efficient
skeletons
in
visible-light-induced
persulfate-promoted
cascade
cyclization
reactions.
With
this
transition-metal-free
photocatalytic
procedure,
various
sulfonated/thiocyanated
pyrrolo[1,2-a]indolediones
synthesized
from
1-acryloyl-2-cyanoindoles
with
sulfonyl
hydrazides/NH4SCN
at
room
temperature
under
mild
reaction
conditions.
The Journal of Organic Chemistry,
Journal Year:
2022,
Volume and Issue:
87(21), P. 14433 - 14442
Published: Oct. 18, 2022
A
visible-light-induced
persulfate-promoted
cascade
phosphorylation/cyclization
reaction
to
access
various
phosphorylated
pyrrolo[1,2-a]indolediones
under
mild
conditions
was
developed.
Notably,
the
transformation
carried
out
with
diethyl
carbonate/H2O
as
a
green
medium
at
room
temperature.
More
impressively,
traditional
metal
catalysts
and
photocatalysts
could
be
effectively
avoided.
The
reactions
are
simple
operate,
easy
scale
up,
have
good
functional
group
tolerance.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(20), P. 7888 - 7893
Published: Oct. 6, 2021
Given
their
omnipresence
in
natural
products
and
pharmaceuticals,
isochromenone
congeners
are
one
of
the
most
privileged
scaffolds
to
synthetic
chemists.
Disclosed
herein
is
a
dual
(ortho/meta)
C-H
C-C
activation
phenacyl
ammonium
salts
(acylammonium
as
traceless
directing
group)
toward
annulation
with
propargylic
alcohols
accomplish
rapid
access
for
novel
isochromenones
by
means
rhodium
catalysis
from
readily
available
starting
materials.
This
operationally
simple
protocol
features
broad
substrate
scope
wide
functional
group
tolerance.
Importantly,
circumvents
need
any
stoichiometric
metal
oxidants
proceeds
under
aerobic
conditions.
The Journal of Organic Chemistry,
Journal Year:
2023,
Volume and Issue:
88(6), P. 3871 - 3882
Published: March 2, 2023
A
palladium-catalyzed
highly
regioselective
C–H
allylation/annulation
reaction
of
N-sulfonyl
amides
with
secondary
or
tertiary
allylic
alcohols
has
been
developed
to
construct
3,4-dihydroisoquinolones
bearing
a
synthetically
valuable
vinyl
substituent.
This
cascade
cyclization
approach
involving
allylation
not
reported
previously.
The
commercially
available
alcohol
substrates,
the
only
by-product
water,
and
used
terminal
oxidant
O2
provide
environmentally
benign
advantages.
Advanced Synthesis & Catalysis,
Journal Year:
2023,
Volume and Issue:
365(21), P. 3713 - 3717
Published: Sept. 16, 2023
Abstract
We
herein
disclose
a
simple
and
general
method
for
the
synthesis
of
chromendiones
through
Rh(III)‐catalyzed
C−H
functionalization/annulation
reactions
nitrones
with
cyclic
2‐diazo‐1,3‐diones
by
using
nitrone
group
as
traceless
directing
group.
This
exhibits
high
efficiency
broad
functional
compatibility.
The
derivatization
these
has
been
also
demonstrated
to
further
strengthen
synthetic
utility
transformation.
Chemical Communications,
Journal Year:
2022,
Volume and Issue:
58(79), P. 11099 - 11102
Published: Jan. 1, 2022
A
novel
strategy
for
the
synthesis
of
2-arylethenesulfonyl
fluorides
from
nitrones
and
ethenesulfonyl
fluoride
(ESF)
by
activation
C-H
bond
using
an
inexpensive
readily
available
Ru-catalyst
has
been
developed.
In
this
process,
directing
group
can
be
concomitantly
converted
to
amide
group.
Interestingly,
changing
substituent
nitrogen
a
tert-butyl
methyl
resulted
in
formation
cyclic
isoindolinones.
Detailed
mechanistic
studies
are
also
presented.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(24), P. 9574 - 9579
Published: Dec. 2, 2021
Five-carbon
(C5)
structural
units
are
the
fundamental
building
blocks
of
many
natural
products.
An
unprecedented
palladium-catalyzed
three-component
dehydrogenative
cascade
coupling
indoles,
2-methylbut-2-ene,
and
carboxylic
acids
has
been
developed.
The
approach
enables
straightforward
introduction
a
C3′-bonded
five-carbon
unit
with
tertiary
alcohol
quaternary
carbon
center
into
indoles.
protocol
employs
2-methylbut-2-ene
as
C5
source
is
featured
by
broad
substrate
scope,
atom
step
economies,
high
chemo-
regioselectivies.
Abstract
A
Pd(II)‐catalyzed
formal
[5+2]
coupling‐cyclization
of
2‐arylbenzaldehydes
with
allylic
alcohols
has
been
developed.
The
method
provides
an
efficient
approach
to
access
diaryl‐fused
cycloheptene
skeletons
via
traceless
α‐amino
acid‐assisted
C
sp
2
−H
activation
process.
