Catalytic enantioselective [3+2] and [4+2]-annulation of cyclic N-sulfonyl ketimines with γ- or δ-hydroxy-α,β-unsaturated ketones
Chemical Communications,
Год журнала:
2024,
Номер
unknown
Опубликована: Янв. 1, 2024
A
highly
efficient
asymmetric
[3+2]
and
[4+2]-annulation
of
cyclic
N
-sulfonyl
ketimines
with
γ-
or
δ-hydroxy-α,β-unsaturated
ketones
has
been
developed.
Язык: Английский
Organocatalytic Enantioselective Synthesis of Polycyclic Benzosultams from 2-Amino-β-nitrostyrenes with Cyclic N-Sulfonyl Ketimines
Organic Letters,
Год журнала:
2024,
Номер
26(7), С. 1472 - 1477
Опубликована: Фев. 13, 2024
A
highly
efficient
enantioselective
[4
+
2]
cycloaddition
of
2-amino-β-nitrostyrenes
with
cyclic
N-sulfonyl
ketimines
has
been
developed.
This
reaction
utilizes
an
organocatalytic
approach,
employing
a
multiple-hydrogen-bonding
bifunctional
squaramide-based
catalyst.
The
process
allows
for
the
precise
synthesis
chiral
polycyclic
benzosultams,
showcasing
intricate
structures
that
incorporate
quaternary
centers.
Noteworthy
outcomes
this
method
include
high
yields
excellent
enantioselectivities
and
diastereoselectivities
(up
to
97%
yield,
96%
ee,
>20:1
dr).
Язык: Английский
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
Improvement of Asymmetric Reactions via Remote Electronic Tuning of N‐Heterocyclic Carbene Catalysts
ChemCatChem,
Год журнала:
2024,
Номер
unknown
Опубликована: Авг. 1, 2024
Abstract
Aminoindanol‐derived
N‐heterocyclic
carbene
catalysts
have
been
widely
used
to
achieve
highly
enantioselective
reactions.
Recently,
substitution
at
the
indane
moiety
of
has
found
a
great
impact
on
outcome
some
reactions,
even
though
substituted
position
is
distant
from
catalytic
center.
Especially,
introduction
an
electron‐withdrawing
group
improves
yield
and
enantioselectivity.
This
review
provides
overview
recent
reports
improvement
N‐heterocyclic‐carbene‐catalyzed
asymmetric
reactions
by
introducing
remote
substituents.
Язык: Английский
[1,5]-Oxy/Thio/Azole Sigmatropic Rearrangement versus Indolyl-Spirocyclization: Tandem Reactions of 2-Azidobenzoate with Isocyanides for Accessing Quinazolin-4(3H)-ones
Organic Letters,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 25, 2024
A
general
protocol
for
the
synthesis
of
a
variety
functionalized
quinazolinones
has
been
developed
through
sequential
Pd-catalyzed
coupling/1,5-alkyloxy/thio/azole
shift/6π
electrocyclization
reaction
isocyanides
and
2-carbonylaryl
azides.
When
3-(2-isocyanoethyl)indoles
were
utilized,
an
unusual
competitive
between
[1,5]-shift
indole-spirocyclization
was
observed,
which
renders
modular
spiroindolenine-3,3'-pyrrolo[2,1-
Язык: Английский