Copper-Catalyzed Formal [4 + 1] Annulation of Diynes with Isoxazoles: Synthesis of Pyrrolo[3,4-b]indoles
Organic Letters,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 14, 2025
Catalytic
annulation
of
isoxazoles
with
alkynes
is
an
efficient
methodology
for
the
assembly
N-heterocyclic
architectures,
and
most
reactions
require
noble-metal
catalysts.
Herein,
we
disclose
a
copper-catalyzed
formal
[4
+
1]
1,6-diynes
atom-economical
construction
biologically
important
pyrrolo[3,4-b]indoles
in
high
yields
via
vinyl
cation
intermediates,
which
significantly
different
from
previous
annulations
involving
α-imino
metal
carbene
intermediates.
Interestingly,
preliminary
results
have
been
obtained
related
catalytic
atroposelective
transformation.
Computational
mechanistic
studies
are
employed
to
elucidate
reaction
mechanism.
Язык: Английский
Ligand‐Dependent Chemoselectivity in Gold‐Catalyzed Reactions between Anthranils and Diynamides. Formation of Spiro Azacyclic Compounds versus 1‐Imino‐1H‐Indene‐3‐Carboximidamides
ChemistryEurope,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 24, 2025
Gold‐catalyzed
reactions
between
anthranils
and
diynamides
have
been
investigated,
their
reaction
chemoselectivity
relies
on
the
types
of
gold
catalysts.
With
same
anthranil/diynamide
mixtures,
use
PPh
3
AuCl/AgNTf
2
leads
to
formation
spiro
azacyclic
compounds,
whereas
P(
t
‐Bu)
(
o
‐biphenyl)AuCl/AgNTf
preferably
yields
1‐imino‐1
H
‐indene‐3‐carboximidamides
instead.
In
system,
an
indole
intermediate
at
low
temperature
for
X‐ray
diffraction
study
is
isolated;
this
isolable
species
requires
anthranil
catalyst
efficient
products.
case
,
mechanism
its
resulting
postulated
based
literature
reports.
Язык: Английский