The Journal of Organic Chemistry,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 18, 2025
The
Alder-ene
reaction
of
the
C-C
bond
in
bicyclo[1.1.0]butanes
would
provide
a
unique
and
efficient
synthesis
route
for
cyclobutene
frameworks.
Herein,
we
report
regio-
diastereoselective
with
β-fluoroalkyl-α,β-unsaturated
ketones,
giving
wide
variety
cyclobutenes
two
contiguous
centers
diene
products.
features
atoms
step
economies
exhibits
broad
substrate
scope.
Several
downstream
transformations
these
were
performed.
Journal of the American Chemical Society,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 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.
Chemical Communications,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 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.
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,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 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.
