Enantioselective Dearomative [2π + 2σ] Photocycloaddition of Naphthalene Derivatives with Bicyclo[1.1.0]butanes Enabled by Gd(III) Catalysis
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.
Язык: Английский
Catalyst-Controlled Regiodivergent Synthesis of Bicyclo[2.1.1]hexanes via Photochemical Strain-Release Cycloadditions
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.
Язык: Английский