Advanced Synthesis & Catalysis,
Journal Year:
2021,
Volume and Issue:
364(4), P. 838 - 844
Published: Dec. 17, 2021
Abstract
A
convenient
and
effective
method
of
ruthenium‐catalyzed
C−H/N−H
annulations
using
vinylene
carbonate
as
oxidizing
acetylene
surrogate
has
been
disclosed.
This
is
scalable
compatible
with
a
wide
range
functional
groups,
providing
step‐economical
access
to
indole
synthesis
Preliminary
mechanistic
studies
provided
support
for
reversible,
acetate‐assisted
C−H
ruthenation,
along
subsequent
olefin
insertion.
magnified
image
ACS Catalysis,
Journal Year:
2020,
Volume and Issue:
10(17), P. 9747 - 9757
Published: Aug. 3, 2020
Transition-metal-catalyzed
C–H
activation
followed
by
oxidative
cyclization
with
unsaturated
coupling
partners
has
been
a
valuable
synthetic
tool
for
the
multiring
molecular
scaffolds.
This
Perspective
introduces
recent
progress
on
Cp*M-catalyzed
(M
=
Co,
Rh,
and
Ir)
direct
annulation
of
functionalized
arenes
terminal
alkynes
their
equivalents
through
bond
cleavage.
The
highlighted
examples
are
categorized
according
to
10
different
types
reagents
used
in
transformations.
representative
conditions,
selected
reaction
scope,
key
mechanistic
aspects
briefly
summarized.
Angewandte Chemie International Edition,
Journal Year:
2021,
Volume and Issue:
60(12), P. 6419 - 6424
Published: Jan. 20, 2021
Abstract
Electrooxidative
annulations
involving
mild
transition
metal‐catalyzed
C−H
activation
have
emerged
as
a
transformative
strategy
for
the
rapid
construction
of
five‐
and
six‐membered
heterocycles.
In
contrast,
we
herein
describe
first
electrochemical
[5+2]
cycloadditions
to
assemble
valuable
seven‐membered
benzoxepine
skeletons
by
C−H/O−H
activation.
The
efficient
alkyne
annulation
featured
ample
substrate
scope,
using
electricity
only
oxidant.
Mechanistic
studies
provided
strong
support
rhodium(III/I)
regime,
benzoxepine‐coordinated
rhodium(I)
sandwich
complex
catalyst
resting
state,
which
was
re‐oxidized
rhodium(III)
anodic
oxidation.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(3), P. 995 - 999
Published: Jan. 27, 2021
In
this
work,
ruthenium(II)-catalyzed
C–C/C–N
annulation
of
2-arylquinazolinones
with
vinylene
carbonate
is
reported
to
synthesize
fused
quinazolinones.
This
catalytic
system
tolerates
a
wide
range
substrates
excellent
functional-group
compatibility.
transformation,
the
acts
as
an
ethynol
surrogate
without
any
external
oxidant
involved.
Furthermore,
preliminary
mechanistic
studies
were
conducted,
and
plausible
cycle
was
also
proposed.
Organic Chemistry Frontiers,
Journal Year:
2021,
Volume and Issue:
8(8), P. 1764 - 1769
Published: Jan. 1, 2021
A
rhodium(iii)-catalyzed
formal
C–H
[5
+
1]
cyclization
of
2-pyrrolyl/indolylanilines
with
vinylene
carbonate
has
been
explored
towards
the
potent
assembly
diverse
4-methylpyrrolo[1,2-a]quinoxalines.
Organic & Biomolecular Chemistry,
Journal Year:
2021,
Volume and Issue:
19(8), P. 1705 - 1721
Published: Jan. 1, 2021
A
review
highlighting
the
advances
in
Cp*Rh(iii)
catalysed
cascade
arene
C–H
activation/annulation
including
application,
scope,
limitations
and
mechanism
of
these
transformations.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(21), P. 8527 - 8532
Published: Oct. 20, 2021
Here
we
report
a
novel
Rh-catalyzed
C−H/C−H
alkenylation
of
N-arylmethanimines
with
vinylene
carbonate
acting
as
unit.
Forty
examples
C3,C4-nonsubstituted
quinolines
were
achieved
from
commercially
available
starting
materials.
This
identified
process
features
an
exceedingly
simple
system,
lower
loading
catalyst,
and
the
capacity
for
postfunctionalization
bioactive
molecules.
Advanced Synthesis & Catalysis,
Journal Year:
2021,
Volume and Issue:
364(3), P. 512 - 517
Published: Nov. 30, 2021
Abstract
The
rhodium(III)‐catalyzed
C−H
bond
activation
and
vinylene
transfer
of
enaminones
with
carbonate
have
been
proposed
for
the
synthesis
substituted
1‐hydroxy‐2‐naphthaldehydes
in
49–84%
yields.
Several
preliminary
mechanistic
studies
hydroxyl‐directed
derivatization
reactions
were
also
performed.
This
method
offers
an
alternative
approach
1‐hydroxy‐2‐naphthaldehydes.
magnified
image
Organic & Biomolecular Chemistry,
Journal Year:
2022,
Volume and Issue:
20(5), P. 1112 - 1116
Published: Jan. 1, 2022
The
direct
synthesis
of
isocoumarin
skeletons
has
been
realized
through
the
Rh(
iii
)-catalyzed
[3
+
3]
annulation
sulfoxonium
ylides
and
iodonium
under
mild
conditions.
Organic Letters,
Journal Year:
2021,
Volume and Issue:
23(14), P. 5518 - 5522
Published: July 6, 2021
The
Rh(III)-catalyzed
C–H
functionalization
and
subsequent
intramolecular
cyclization
between
azobenzenes
vinylene
carbonate
is
described
herein.
Depending
on
the
electronic
property
of
azobenzenes,
this
transformation
results
in
formation
(2H)-indazoles
or
dihydrocinnolin-4-ones
through
generation
ortho-alkylated
azo-intermediates
followed
by
decarboxylation.
Surprisingly,
acts
as
an
acetaldehyde
acetyl
surrogate
to
enable
[4
+
1]
2]
annulation
reaction.
This
characterized
its
mild
reaction
conditions,
simplicity,
excellent
functional
group
compatibility.
