Intramolecular [2+2+2] Cyclotrimerization of a Model Triyne to [7]Helical Indeno[2,1-c]Fluorene with Air-Stable Ni(0) and Other Precatalysts
Catalysts,
Год журнала:
2025,
Номер
15(2), С. 150 - 150
Опубликована: Фев. 5, 2025
In
this
work,
we
demonstrated
that
air-stable
Ni(0)
complexes
with
phosphine
ligands
can
effectively
catalyze
intramolecular
cyclotrimerization
of
a
triyne
to
compound
[7]helical
indeno[2,1-c]fluorene
skeleton.
The
obtained
results
are
comparable
those
achieved
by
using
Rh-based
catalytic
systems.
Screening
the
reaction
conditions
showed
bidentate
small
bite
angles
(70–80°)
gave
best
in
terms
yields.
highest
asymmetric
induction
investigated
precatalyst
was
PROPHOS
ligand
HFIP
(62%
ee).
Other
systems,
like
[Rh(CH2=CH2)2Cl]2
and
[CpCo(P{OEt}3)(trans-MeO2CHC=CHCO2Me)],
have
also
been
investigated,
showing
promising
results.
Язык: Английский
Chiral Brønsted Acid‐Catalyzed Asymmetric Reaction via Vinylidene Ortho‐Quinone Methides
Chemistry - A European Journal,
Год журнала:
2024,
Номер
30(49)
Опубликована: Июнь 26, 2024
Vinylidene
ortho-quinone
methides
(VQMs)
have
been
proven
to
be
versatile
and
crucial
intermediates
in
the
catalytic
asymmetric
reaction
last
decade,
thus
drawn
considerable
concentrations
on
account
of
practical
application
construction
enantiomerically
pure
functional
organic
molecules.
However,
comparison
well
established
chiral
Brønsted
base-catalyzed
via
VQMs,
acid-catalyzed
is
rarely
studied
there
no
systematic
summary
date.
In
this
review,
we
summarize
recent
advances
VQMs
according
three
types
reactions:
a)
intermolecular
nucleophilic
addition
VQMs;
b)
cycloaddition
c)
intramolecular
cyclization
VQMs.
Finally,
put
forward
remained
challenges
opportunities
for
potential
breakthroughs
area.
Язык: Английский