Organic Letters,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 26, 2024
A
palladium-catalyzed
[2π
+
2σ]
cycloaddition
of
vinyl
bicyclo[1.1.0]butanes
with
methyleneindolinones
has
been
developed.
The
reaction
enables
the
construction
spirobicyclo[2.1.1]hexanes
bearing
an
all-carbon
quaternary
center
in
moderate
to
good
yields
excellent
diastereoselectivities.
This
method
features
a
broad
substrate
scope
functional
group
compatibility.
practical
utility
this
protocol
was
further
demonstrated
by
gram-scale
synthesis
and
postsynthetic
transformations
desired
product.
Organic Letters,
Journal Year:
2024,
Volume and Issue:
26(43), P. 9311 - 9315
Published: Oct. 17, 2024
Dearomative
cycloadditions
are
valuable
for
efficiently
generating
three-dimensional
molecular
complexity.
However,
despite
recent
reports
of
bicyclobutanes
(BCBs)
the
synthesis
aza-bicyclo[3.1.1]heptanes
(aza-BCHeps),
which
bioisosteres
Chemical Science,
Journal Year:
2024,
Volume and Issue:
15(46), P. 19488 - 19495
Published: Jan. 1, 2024
We
present
the
first
enantioselective
dearomative
(3+3)
cycloadditions
of
bicyclobutanes
(BCBs)
utilizing
a
chiral
Lewis
acid
catalyst
and
bidentate
chelating
BCB
substrates.
Chemical Science,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 13, 2024
This
manuscript
presents
a
photoredox-catalyzed
defluorinative
(4
+
3)
annulation
of
bicyclo[1.1.0]butanes
with
gem
-difluoroalkenes,
providing
practical
and
straightforward
access
to
the
fluorine-containing
bicyclo[4.1.1]octenes.
Chemical Communications,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 1, 2025
Herein
we
report
a
simple
BF
3
-catalyzed
cycloaddition
of
dihydropyridines
with
bicyclobutanes
for
the
expedient
synthesis
novel
three-dimensional
azacycle-fused
bicyclo[2.1.1]hexane
scaffolds.
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 28, 2025
The
cycloaddition
reactions
of
bicyclo[1.1.0]butanes
with
alkenes,
imines,
nitrones,
or
aziridines
have
served
as
an
efficient
platform
to
create
conformationally
restricted
saturated
bicyclic
scaffolds.
However,
the
use
readily
available
aromatics
in
such
reactions,
especially
asymmetric
manner,
remains
underexplored.
Herein,
we
report
a
highly
regio-
and
enantioselective
dearomative
[2π
+
2σ]
photocycloaddition
reaction
between
naphthalene
derivatives
bicyclo[1.1.0]butanes,
enabled
by
Gd(III)
catalysis.
Bicyclo[1.1.0]butanes
naphthalenes
adorned
diverse
array
functional
groups
are
well-tolerated
under
mild
conditions,
affording
enantioenriched
pharmaceutically
important
bicyclo[2.1.1]hexanes
30–96%
yields
81–93%
ee
12:1
→
>20:1
rr.
synthetic
versatility
this
is
further
demonstrated
facile
removal
directing
group
derivatizations
dearomatized
product.
UV–vis
absorption
spectroscopy
studies
suggest
involvement
excited
species
process.
Organic Letters,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 1, 2025
Multiply
substituted
cyclobutanols
are
pivotal
synthetic
intermediates
for
constructing
complex
molecular
architectures
via
ring-opening
strategies.
The
development
of
efficient
methods
these
valuable
building
blocks
has
garnered
significant
interest
in
the
chemical
community.
In
this
work,
we
have
described
a
novel
silver(I)-catalyzed
tandem
cyclization–cycloaddition–isomerization
sequence
with
bicyclobutanes
and
2-alkynylbenzaldoximes,
which
offered
an
effective
route
to
multiply
cyclobutanols.
This
protocol
features
mild
conditions,
remarkable
stereospecificity,
broad
substrate
scope,
excellent
functional
group
tolerance.
addition,
application
potential
reaction
was
readily
proven
by
its
high
efficiency
reactants
bearing
biological
moieties
scale-up
experiments.
Organic Letters,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 8, 2025
Higher-order
cycloadditions
are
a
simple
and
effective
strategy
for
constructing
significant
medium-sized
architectures.
Azaheptafulvenes
reacting
with
readily
accessible
bicyclo[1.1.0]butanes
(BCBs)
through
FeCl3-promoted
intermolecular
formal
[8π+2σ]
cycloaddition
reactions
to
access
cycloheptatriene-fused
2-azabicyclo[3.1.1]heptanes
have
been
developed.
This
new
reaction
tolerated
wide
range
of
azaheptafulvenes
BCBs.
Furthermore,
the
amplification
experiment
synthetic
transformations
adducts,
including
modifications
marketed
drugs,
further
highlighted
their
practicalities.
Control
experiments
DFT
calculations
suggest
that
diastereoselective
product
formation
may
involve
stepwise
pathway.
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 23, 2025
Bicyclo[2.1.1]hexane
is
an
emerging
scaffold
in
various
pharmaceutical
settings,
but
the
scarcity
of
approaches
to
target
different
regioisomers
from
a
common
starting
material
prevents
targeting
broader
range
chemical
space.
Herein,
we
demonstrate
new
design
for
photocatalyst-controlled
regiodivergent
synthesis
this
scaffold.
Of
particular
interest
that
two
distinct
substitution
patterns
was
achieved
under
photochemical
conditions
with
catalyst
control.
This
possible
due
activating
group,
N-methylimidazole,
not
only
playing
important
role
guiding
divergent
pathways
also
enabling
transformation
functional
groups.
Transient
absorption
spectroscopy
discerned
between
mechanisms,
as
assignable
bands
consistent
electron
transfer
and
energy
processes
were
distinctively
observed,
depending
on
identity
photocatalyst.
