European Journal of Organic Chemistry,
Год журнала:
2023,
Номер
27(3)
Опубликована: Ноя. 6, 2023
Abstract
A
cobalt‐catalyzed
annulation
of
o
‐phenylenediamines
and
internal
alkynes
for
the
synthesis
quinoxalines
is
developed.
This
method
provides
a
variety
in
good
to
high
yields
under
simple
mild
reaction
conditions
with
molecular
O
2
as
terminal
oxidant.
Preliminary
mechanistic
studies
show
that
novel
mechanism
involved
current
reaction,
which
different
from
previous
reported
dicarbonyl
compound
via
oxidation
alkyne.
Chemical Science,
Год журнала:
2023,
Номер
14(21), С. 5705 - 5711
Опубликована: Янв. 1, 2023
[1,3]-Nitrogen
rearrangement
reactions
of
O
-aryl
ketoximes
was
catalytically
promoted
by
IPrCuBr
and
BF
3
·OEt
2
.
The
oxidative
addition
the
N–O
bond
to
Cu
catalyst
is
accelerated
donation
electrons
from
both
nitrogen
oxygen
atoms.
European Journal of Organic Chemistry,
Год журнала:
2024,
Номер
27(12)
Опубликована: Янв. 19, 2024
Abstract
A
catalytic
carbonylative
method
for
the
direct,
multicomponent
synthesis
of
indolizine
fluorophores
has
been
developed.
The
process
is
based
on
PdI
2
/KI‐catalyzed
oxidative
aminocarbonylation
2‐(pyridin‐2‐yl)pent‐4‐yn‐1‐carbonyl
compounds
leading
to
corresponding
2‐ynamide
intermediates,
followed
in
situ
by
5‐
exo
‐
dig
cyclization
(by
amine‐promoted
conjugate
addition
pyridine
ring
nitrogen)
and
aromatization,
give
finally
isolated
N
,
‐disubstituted
2‐(indolizin‐3‐yl)acetamides.
Reactions
are
carried
out
under
relatively
mild
conditions
(100
°C
20
atm
a
4
:
1
mixture
CO−air
6–15
h)
MeCN
as
solvent
with
low
catalyst
loading
(0.33
mol%
),
presence
0.5
equiv.
KI
3
secondary
amine.
optical
properties
representative
2‐(indolizin‐3‐yl)acetamide
products
have
also
investigated.
Asian Journal of Organic Chemistry,
Год журнала:
2022,
Номер
11(12)
Опубликована: Ноя. 1, 2022
Abstract
The
β‐Csp
3
−H
functionalization
of
N‐sulfonyl
ketimines
with
2‐(2‐enynl)pyridines/quinolines
via
a
cooperative
Ag(I)‐/organobase‐catalyzed
5‐
endo‐dig
cyclization‐addition
reaction
is
reported.
This
successive
C−N/C−C
bond‐making
provides
simple
and
atom‐economical
technique
for
granting
diverse
set
1,3‐disubstituted
indolizines/pyrrolo[1,2‐
]quinolines
possessing
synthetically
resourceful
ketimine
moiety.
Moreover,
our
designed
strategy
applies
to
broad
substrates
allows
various
functionalities.
Furthermore,
this
has
many
imperative
synthetic
points
such
as
mild
conditions,
low
catalyst
loading,
acceptable
chemical
yields
highly
diastereoselective
(up
≤93
:
7
dr).
moiety
indolizine
was
easily
transmuted
into
the
reputed
classes
coumarin
benzofuran
derivatives.
European Journal of Organic Chemistry,
Год журнала:
2023,
Номер
27(3)
Опубликована: Ноя. 6, 2023
Abstract
A
cobalt‐catalyzed
annulation
of
o
‐phenylenediamines
and
internal
alkynes
for
the
synthesis
quinoxalines
is
developed.
This
method
provides
a
variety
in
good
to
high
yields
under
simple
mild
reaction
conditions
with
molecular
O
2
as
terminal
oxidant.
Preliminary
mechanistic
studies
show
that
novel
mechanism
involved
current
reaction,
which
different
from
previous
reported
dicarbonyl
compound
via
oxidation
alkyne.
