Synthesis of Polycyclic Imidazolidinones via Cascade [3 + 2]-Annulation of β-Oxo-acrylamides with Cyclic N-Sulfonyl Imines
Lei Xie,
Chenyi Zhao,
Zhaoxue Wang
и другие.
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(22), С. 15805 - 15816
Опубликована: Окт. 31, 2023
An
Et3N-catalyzed
cascade
[3
+
2]-annulation
of
β-oxo-acrylamides
with
cyclic
N-sulfonyl
ketimines
or
sulfamate-derived
imines
is
developed
under
mild
reaction
conditions,
which
provides
a
concise
and
efficient
route
to
access
valuable
sultam-
sulfamidate-fused
imidazolidinone
derivatives
in
good
excellent
yields
(80–95%
yields)
diastereoselectivities
(>20:1
drs).
The
current
protocol
features
atom
economy,
transition-metal-free
process,
broad
functional
group
tolerance.
Moreover,
the
asymmetric
variant
2]-cycloaddition
was
achieved
presence
diphenylethanediamine
quinine-based
bifunctional
squaramide
organocatalysts
C-1
C-11,
giving
corresponding
chiral
polycyclic
imidazolidinones
68–90%
25–94%
ees
>20:1
drs
all
cases.
Язык: Английский
Thiol-Triggered Tandem Dearomative Michael Addition/Intramolecular Henry Reaction of 2-Nitrobenzofurans: Access to Sulfur-Containing Polyheterocyclic Compounds
Organic Letters,
Год журнала:
2024,
Номер
26(13), С. 2623 - 2628
Опубликована: Март 24, 2024
An
efficient
dearomative
cyclization
of
2-nitrobenzofurans
via
a
thiol-triggered
tandem
Michael
addition/intramolecular
Henry
reaction
has
been
developed.
A
range
thiochromeno[3,2-b]benzofuran-11-ols
and
tetrahydrothieno[3,2-b]benzofuran-3-ols
could
be
obtained
in
up
to
99%
yield
>20:1
dr.
The
valuable
thiochromone
fused
benzofurans
prepared
with
the
2-mercaptobenzaldehyde
reaction/rearomatization/oxidative
dehydrogenation
process
one-pot
two-step
operation.
mechanism
for
was
tentatively
proposed.
Язык: Английский
Synthesis of Benzofuro[3,2-b]indol-3-one Derivatives via Dearomative (3 + 2) Cycloaddition of 2-Nitrobenzofurans and para-Quinamines
Molecules,
Год журнала:
2024,
Номер
29(5), С. 1163 - 1163
Опубликована: Март 5, 2024
An
efficient
dearomative
(3
+
2)
cycloaddition
of
para-quinamines
and
2-nitrobenzofurans
has
been
developed.
This
reaction
proceeds
smoothly
under
mild
conditions
affords
a
series
benzofuro[3,2-b]indol-3-one
derivatives
in
good
to
excellent
yields
(up
98%)
with
perfect
diastereoselectivities
(all
cases
>
20:1
dr).
The
scale-up
synthesis
versatile
derivatizations
demonstrate
the
potential
synthetic
application
protocol.
A
plausible
mechanism
is
also
proposed
account
for
observed
process.
work
represents
first
instance
N-triggered
2-nitrobenzofurans.
Язык: Английский
Copper-Catalyzed Annulation of Electrophilic Benzannulated Heterocycles with 2-Aminopyridine and 2-Aminoquinoline: Direct Access toward Polyring-Fused Imidazo[1,2-a]pyridines
The Journal of Organic Chemistry,
Год журнала:
2023,
Номер
88(14), С. 10027 - 10039
Опубликована: Июль 11, 2023
We
have
developed
a
direct
method
for
the
synthesis
of
polyring-fused
imidazo[1,2-a]pyridines
via
copper-catalyzed
annulation
electrophilic
benzannulated
heterocycles
with
2-aminopyridine
and
2-aminoquinoline.
From
3-nitroindoles
2-aminopyridine,
we
could
synthesize
tetracenes,
viz.,
indole-fused
imidazo[1,2-a]pyridines,
by
starting
from
2-aminoquinoline,
generate
pentacenes,
indolo-imidazo[1,2-a]quinolines.
In
addition,
also
extend
methodology
toward
benzothieno-imidazo[1,2-a]pyridines
3-nitrobenzothiophene.
Furthermore,
basic
photophysical
properties
these
synthesized
heteroacenes
were
evaluated.
Язык: Английский
Organocatalytic cascade nucleophilic/aza-Michael addition reactions: metal-free catalytic strategy for the synthesis of hydantoins
Organic & Biomolecular Chemistry,
Год журнала:
2022,
Номер
21(11), С. 2295 - 2300
Опубликована: Ноя. 17, 2022
Lewis
base-catalyzed
cascade
nucleophilic/aza-Michael
addition
reaction
of
N-alkoxy
β-oxo-acrylamides
with
isocyanates
has
been
developed
to
afford
various
highly
functionalized
hydantoin
derivatives
in
80-98%
yields
under
mild
conditions.
The
intriguing
features
this
method
include
metal-free
conditions,
low
catalyst
loading,
broad
substrate
scope
and
short
time.
Язык: Английский
Lewis base-catalyzed cascade [4 + 2]-annulation reaction of N-alkoxy acrylamides and acyl isothiocyanates: facile access to 2-imino-1,3-thiazinone derivatives
Organic & Biomolecular Chemistry,
Год журнала:
2023,
Номер
21(46), С. 9200 - 9209
Опубликована: Янв. 1, 2023
A
Lewis
base-catalyzed
cascade
aza-nucleophilic
addition/thio-Michael
addition
reaction
of
N
-alkoxy
acrylamides
with
acyl
isothiocyanates
has
been
developed
to
afford
various
2-imino-1,3-thiazinone
derivatives
in
40–97%
yields.
Язык: Английский
Additive‐Controlled Divergent [4+2] Cycloaddition and 1,4‐Michael Addition Reaction of Benzofuran‐Derived Azadienes with Enamides: Access to Decahydrobenzofuro[3,2‐b]quinolines
ChemistrySelect,
Год журнала:
2024,
Номер
9(26)
Опубликована: Июль 9, 2024
Abstract
We
describe
herein
the
additive‐controlled
divergent
[4+2]
cycloaddition
and
1,4‐Michael
addition
reaction
of
benzofuran‐derived
azadienes
(BDAs)
with
enamides.
An
unprecedented
BDAs
enamide
compounds
was
developed
in
presence
4
Å
MS,
providing
a
variety
structurally
complex
decahydrobenzofuro[3,2‐
b
]quinolines
(13
examples)
moderate
to
excellent
yields
(59–98
%
yields)
single
diastereoisomer
obtained.
While
employing
MgSO
as
desiccant,
chemoselectivity
switched
1,4‐addition
reactions,
leading
wide
range
highly
functionalized
hybrids
benzofurans
(25
25–94
under
mild
conditions.
Язык: Английский
Formal Alkenylation and Amination of 2‐Nitrobenzofurans with Fumaric Acid Amide Ester under Metal‐Free Conditions
ChemistrySelect,
Год журнала:
2023,
Номер
8(1)
Опубликована: Янв. 4, 2023
Abstract
An
inorganic
base
promoted
metal‐free
formal
alkenylation
and
amination
of
2‐nitrobenzofurans
is
established
with
fumaric
acid
amide
ester
derivatives.
The
cascade
strategy
provides
the
2‐alkenyl
3‐amino
substituted
benzofurans
via
Michael
addition/cyclization/nitrous
elimination/
N
‐demethoxylation/C−N
bond
cleavage
isomerization
sequence.
desired
2‐(3‐aminobenzofuran‐2‐yl)malonate
derivatives
are
obtained
in
moderate‐to‐good
yields
high
stereoselectivity
under
mild
reaction
conditions
(up
to
71
%
yield
>20
:
1
Z
E
).
structure
products
assigned
from
single
crystal
x‐ray
structural
analysis.
Язык: Английский