Enantioselective Synthesis of Tetrahydro-1H-1,3-methanocarbazoles by Formal (3 + 3)-Cycloaddition Using Bicyclo[1.1.0]butanes
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 28, 2025
Asymmetric
synthesis
presents
many
challenges,
with
the
selective
formation
of
chiral
bridged
polyheterocycles
being
a
notable
example.
Cycloadditions
using
bicyclo[1.1.0]butanes
(BCB)
offer
promising
solution
along
those
lines,
yet,
despite
significant
advances
in
that
emerging
area,
asymmetric
control
has
remained
limited
thus
far.
Here,
we
describe
an
organocatalytic,
enantioselective
formal
(3
+
3)-cycloaddition
BCBs
1H-indol-3-yl((hetero)aryl)methanol
derivatives.
This
approach
enables
rapid
and
efficient
tetrahydro-1H-1,3-methanocarbazole
derivatives
(34
examples)
from
readily
available
starting
materials,
very
good
stereochemical
(up
to
98:2
er).
Successful
scale-up
experiments
product
modification
demonstrated
potential
this
methodology.
Control
DFT
calculations
provide
insights
into
mechanistic
pathway.
Language: Английский
Titanocene dichloride-catalyzed synthesis of heterocycles accelerated by in-situ formed Lewis and Brønsted acids
Yuanyong Yao,
No information about this author
Li Tu,
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Xiu Wang
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et al.
Molecular Catalysis,
Journal Year:
2025,
Volume and Issue:
573, P. 114822 - 114822
Published: Jan. 18, 2025
Language: Английский
Lewis Acid-Catalyzed Enantioselective (4 + 3)/Thia-(3 + 2) Cycloadditions of Bicyclobutanes and Enaminothiones: Catalyst-Directed Divergent Synthesis of Bridged Sulfur Heterocycles
Lei Tang,
No information about this author
Wenjuan Bai,
No information about this author
Keqing Wang
No information about this author
et al.
ACS Catalysis,
Journal Year:
2025,
Volume and Issue:
unknown, P. 7877 - 7890
Published: April 28, 2025
Language: Английский
Stereocontrolled Synthesis of Cyclobutylamines Enabled by Lewis Acid-Catalyzed (3 + 2 + 2) Cycloaddition/Ring-Opening Strategy of Bicyclo[1.1.0]butanes with Triazinanes
Yijun Duan,
No information about this author
Feng Chen,
No information about this author
Ye Guo
No information about this author
et al.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 2, 2024
Herein,
we
develop
a
modular
and
efficient
"cycloaddition/ring-opening"
strategy
of
bicyclo[1.1.0]butanes
(BCBs)
with
triazinanes
to
provide
series
syn-diastereoselective
cyclobutylamines
via
2,4-diazabicyclo[4.1.1]octanes
(aza-BCOs).
The
reaction
features
simple
operation,
mild
conditions,
broad
substrate
scope.
Mechanistic
studies
suggest
that
the
cycloaddition
follows
stepwise
(3
+
2
2)
rather
than
(4
3)
cycloaddition,
involving
an
SN2
nucleophilic
addition
formaldimine
Lewis
acid-activated
BCB
species.
A
scale-up
experiment
various
synthetic
transformations
product
further
highlight
utility.
We
expect
our
findings
will
encourage
exploration
chemistry
access
more
synthetically
challenging
cyclobutane
frameworks.
Language: Английский