ACS Catalysis,
Год журнала:
2017,
Номер
7(10), С. 7296 - 7304
Опубликована: Сен. 12, 2017
An
efficient,
atom-economical,
and
regioselective
insertion
of
indoles
into
terminal
alkynes
has
been
realized
via
cobalt(III)-catalyzed
C–H
activation
under
mild
conditions,
leading
to
efficient
synthesis
α-gem-vinylindoles.
The
the
follows
a
rare
1,2-selectivity,
silyl
alkynes,
alkyl
propargyl
alcohols,
protected
amines
are
all
applicable.
mechanism
this
hydroarylation
system
studied
in
detail
by
combination
experimental
computational
approaches.
In
reaction
regioselectivity
is
dictated
steric
effects
alkyne
substituent,
especially
protonolysis
stage.
However,
for
amines,
selectivity
results
from
electronic
during
step,
with
being
insignificant
determination
selectivity.
internal
also
coupled
high
efficiency
but
low
regioselectivity.
Comparisons
cobalt,
rhodium,
iridium
catalysts
have
made
terms
reactivity,
both
cobalt
catalysts.
Chemistry - A European Journal,
Год журнала:
2017,
Номер
23(50), С. 12149 - 12152
Опубликована: Июнь 11, 2017
Herein,
we
report
a
Cp*CoIII
-catalyzed
C-H
activation
approach
as
the
key
step
to
create
highly
valuable
isoquinolones
and
pyridones
building
blocks
that
can
readily
be
applied
in
total
syntheses
of
variety
aromathecin,
protoberberine,
tylophora
alkaloids.
This
particular
activation/annulation
reaction
was
achieved
with
several
terminal
well
internal
alkyne
coupling
partners
delivering
broad
scope
excellent
functional
group
tolerance.
The
synthetic
applicability
this
protocol
reported
herein
demonstrated
two
Topo-I-Inhibitors
8-oxyprotoberberine
cores
further
elaborated
into
tetrahydroprotoberberine
protoberberine
alkaloid
core.
Moreover
these
were
also
transformed
six
different
alkaloids
expedient
fashion.
Organic Letters,
Год журнала:
2018,
Номер
20(18), С. 5981 - 5984
Опубликована: Сен. 12, 2018
A
Cp*Co(III)-catalyzed
C-H
bond
functionalization
of
a
range
arenes
by
employing
sulfoxonium
ylides
as
carbene
precursors
instead
diazo
compounds
and
other
has
been
established.
This
reaction
is
highly
efficient
without
any
additive,
possesses
high
step
atom
economies,
tolerates
functional
groups.
