We
report
here
a
Rh(III)
catalysed
regio-
and
stereo-selective
synthesis
of
alkynylated
bis-iso-
coumarin
from
1,3-dialkyne.
Exclusive
one-pot
formation
3,3-bis-isocoumarin
isomer
has
been
achieved
by
elim-
inating
several
other
possibilities.
This
is
the
first
example
transition
metal
catalyzed
bis-isocoumarin
scaffold.
The
protocol
compatible
with
wide
range
functional
groups
affording
good
to
excel-
lent
yields.
Several
mechanistic
investigations
including
deuterium
labeling
experiment
kinetic
isotope
effect
study
have
carried
out.
Journal of the American Chemical Society,
Год журнала:
2023,
Номер
145(6), С. 3588 - 3598
Опубликована: Фев. 3, 2023
Catalytic
enantioselective
functionalization
of
cyclobutenes
constitutes
a
general
and
modular
strategy
for
construction
enantioenriched
complex
cyclobutanes
bearing
multiple
stereogenic
centers,
as
chiral
four-membered
rings
are
common
motifs
in
biologically
active
molecules
versatile
intermediates
organic
synthesis.
However,
synthesis
through
such
remained
significantly
limited.
Herein,
we
report
series
unprecedented
cobalt-catalyzed
carbon-carbon
bond
forming
reactions
that
initiated
carbometalation.
The
protocols
feature
diastereo-
introduction
allyl,
alkynyl,
functionalized
alkyl
groups.
Mechanistic
studies
indicated
an
unusual
1,3-cobalt
migration
subsequent
β-carbon
elimination
cascade
process
occurred
the
allyl
addition.
These
new
discoveries
established
elementary
cobalt
catalysis
extension
diversity
nucleophiles
transformations
cyclobutenes.
ACS Catalysis,
Год журнала:
2022,
Номер
12(21), С. 13247 - 13281
Опубликована: Окт. 17, 2022
In
recent
years,
transition
metal-catalyzed
strong
C–C
bond
activation
has
significantly
attracted
the
attention
of
synthetic
chemists.
This
protocol
enables
simultaneous
and
direct
functionalization
two
different
M–C
bonds.
Among
types
strategies,
strain-driven
resulted
in
various
otherwise
difficult
transformations.
this
context,
palladium
catalyst
been
extensively
used
studied
due
to
its
robust
reactivity
selectivity.
Herein
we
have
briefly
discussed
palladium-catalyzed
three-
four-membered
cycloalkane
derivatives.
European Journal of Organic Chemistry,
Год журнала:
2024,
Номер
27(9)
Опубликована: Фев. 8, 2024
Abstract
Cycloalkanols
ring‐opening
transformation
is
one
of
the
most
valuable
and
wide
area
research.
Among
numerous
methods
that
have
been
developed,
transition‐metal‐free
approaches
attracted
great
interest
from
both
chemists
pharmacologists.
This
largely
due
to
advantages
being
environmentally
benign,
cost‐effective
operationally
simple.
Here
we
provide
a
comprehensive
outline
on
recent
advances
in
synthesis
distally
substituted
ketones
cyclic
compounds
via
cycloalkanols
under
conditions.
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(14), С. 2842 - 2869
Опубликована: Янв. 1, 2023
The
1,3-diynes
hold
a
prominent
position
among
the
many
coupling
partners
employed
in
metal-catalysed
C–H
activation
because
of
their
ability
to
form
complex
bis-heterocycles
one
shot.
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(13), С. 8722 - 8737
Опубликована: Июнь 14, 2023
A
phosphine-catalyzed
ring-opening
addition
reaction
of
cyclopropenones
with
a
variety
nucleophiles
(NuH),
including
oxygen-,
nitrogen-,
sulfur-,
and
carbon-based
ones,
has
been
investigated,
which
produces
potentially
useful
α,β-unsaturated
carbonyl
derivatives
in
high
yields
(up
to
99%),
regioselectivity,
exclusive
E-selectivity.
The
proceeds
efficiency
under
very
mild
conditions
using
only
1
mol
%
PPh3
as
the
catalyst
at
room
temperature.
method
is
also
amenable
for
synthesis
deuterated
alkenes
when
(NuD)
are
employed.
mechanism
investigated
by
experiments
DFT
calculations,
suggests
an
α-ketenyl
phosphorus
ylide
key
intermediate
catalytic
cycle
that
captures
stereoselective
manner.
Abstract
Cyclopropanols,
due
to
their
particular
chemistry,
can
participate
in
various
synthetic
reactions
with
retention
or
cleavage
of
the
strained
three‐membered
ring.
Direct
cross‐coupling
ring‐opening
reaction
such
molecules
access
organic
compounds,
as
ketones
has
great
importance
medicinal
chemistry
and
material
sciences.
Hence,
coupling
reaction/cyclization
cyclopropanols
for
constructing
new
valuable
presence
a
transition
metal
catalyst
under
metal‐free
conditions
is
described
this
context.
The
features
are
discussed,
mechanisms
challenging
highlighted.
We
report
herein
a
chelation
assisted,
ring-strain-driven
homoenolate
interception
with
allenamides,
proceeding
through
complementary
reactivity
pattern─noncycloaddition
and
central
C
of
C-pronucleophiles─distinct
from
previous
studies.
The
developed
atom-economical
method
provides
access
to
carbonyl-tagged
enamides
high
chemo-
regioselectivity,
offering
broad
scope
significant
synthetic
value,
as
demonstrated
by
further
diversification.
origin
the
selectivity
is
clarified
experimental
mechanistic
investigations,
revealing
detailed
reaction
pathway
carbopalladation
event.
Advanced Synthesis & Catalysis,
Год журнала:
2022,
Номер
364(15), С. 2540 - 2545
Опубликована: Июнь 25, 2022
Abstract
An
one‐pot
three‐component
synthesis
of
benzofuran‐3(2
H
)‐ones
with
tetrasubstituted
carbon
stereocenters
from
salicylaldehydes,
cyclopropanols,
and
alkyl
alcohols
via
Rh(III)‐catalyzed
C−H/C−C
bond
activation
cascade
annulation
has
been
successfully
developed.
magnified
image
ACS Catalysis,
Год журнала:
2023,
Номер
13(7), С. 4362 - 4368
Опубликована: Март 15, 2023
The
transition-metal-catalyzed
intramolecular
hydroarylation
of
alkenes
has
been
recognized
as
a
straightforward
approach
for
the
construction
3,3-disubstituted
2,3-dihydrobenzofurans.
reactions
mainly
rely
on
reductive
Heck
reaction
aryl
halides
or
direct
C–H
bond
activation
arenes
bearing
directing
group.
This
work
realizes
Rh-catalyzed
olefin-tethered
benzocyclobutenols
via
C–C
activation,
which
offers
an
alternative
to
2,3-dihydrobenzofurans
4-β-keto
moiety.
methodology
features
100%
atom
economy
and
pH-
redox-neutral
conditions,
is
applicable
late-stage
functionalization
complex
molecules.
asymmetric
variant
also
achieved
with
excellent
enantioselectivities.
Organic Letters,
Год журнала:
2024,
Номер
26(30), С. 6314 - 6319
Опубликована: Июль 22, 2024
The
regio-/stereoselective
synthesis
of
vinyl
cyclobutanols
from
alkynyl
is
demonstrated.
Here,
selective
C-C
bond
activation
the
cyclopropyl
alcohol
ring
has
been
achieved
in
presence
cyclobutanol
ring.
KIE
experiments
indicated
noninvolvement
O-H
oxidative
addition
step
rate-determining
step.
Further,
applicability
these
for
1,4-diketones
and
1,6-diketone
