Angewandte Chemie,
Год журнала:
2024,
Номер
136(42)
Опубликована: Июль 20, 2024
Abstract
Introduction
of
non‐hexagons
and/or
heteroatoms
allows
for
finely
tuning
the
physicochemical
properties
nanographenes.
Heteroatoms
doping
have
dominated
modulation
nanographenes
with
tunable
band
gap,
rich
electrochemical
activities
and
so
on.
The
pair
non‐hexagons,
instance,
pentagon‐heptagon
pairs,
furnished
aromatic
antiaromatic
characteristics,
open‐shell
In
order
to
meet
growing
demand
versatile
in
materials
science,
research
on
novel
heteroatom
doped
non‐hexagonal
pairs
has
been
aroused
recent
years.
this
review,
we
focus
nitrogen‐doped
paris
including
synthesis,
structure
analysis,
photophysical
properties,
potential
applications
organic
devices.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(23), С. 16161 - 16172
Опубликована: Май 9, 2024
Introducing
helical
subunits
into
negatively
curved
π-systems
has
a
significant
effect
on
both
the
molecular
geometry
and
photophysical
properties;
however,
synthesis
of
these
embedded
with
nonbenzenoid
remains
challenging
due
to
high
strain
deriving
from
curvature
helix.
Here,
we
report
family
nonalternant
nanographenes
containing
nitrogen
(N)-doped
cyclopenta[ef]heptalene
unit.
Among
them,
CPH-2
CPH-3
can
be
viewed
as
hybrids
benzoannulated
aza[7]helicene.
The
crystal
structures
revealed
saddle
for
CPH-1,
saddle-helix
hybrid
CPH-2,
twist-helix
CPH-3.
Experimental
measurements
theoretical
calculations
indicate
that
moieties
in
CPHs
undergo
flexible
conformational
changes
at
room
temperature,
while
aza[7]helicene
subunit
exhibits
dramatically
increased
racemization
energy
barrier
(78.2
kcal
mol–1
143.2
CPH-3).
combination
lone
electron
pairs
N-doped
unit
twisted
helix
fragments
results
rich
photophysics
distinctive
fluorescence
phosphorescence
CPH-1
similar
Both
enantiopure
display
distinct
circular
dichroism
(CD)
signals
UV–vis
range.
Notably,
compared
reported
fully
π-extended
nanographenes,
excellent
chiroptical
properties
|gabs|
value
1.0
×
10–2
|glum|
7.0
10–3;
values
are
among
highest
nanographenes.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 11, 2024
Abstract
The
synthesis
of
fully
fused
π‐conjugated
cycloarenes
embedded
with
nonbenzenoid
aromatics
is
challenging.
In
this
work,
the
first
example
four‐membered
ring‐embedded
cycloarene
(
MF2
)
was
designed
and
synthesized
in
single‐crystal
form
by
macrocyclization
ring
fusion
strategies.
For
comparison,
single
bond‐linked
chiral
macrocycle
MS2
without
two
rings
its
linear‐shaped
polycyclic
benzenoid
monomer
L1
were
also
synthesized.
pronounced
anti‐aromaticity
significantly
adjusts
electronic
structures
photophysical
properties
cycloarene,
resulting
an
enhancement
photoluminescence
quantum
yield
(PLQY)
from
10.66
%
10.74
for
,
respectively,
to
54.05
which
highest
PLQY
among
reported
cycloarenes.
Notably,
owing
anti‐aromatic
that
reduce
structural
displacements,
exhibits
ultra‐narrowband
emission
a
single‐digit
full‐width
at
half‐maximum
(FWHM)
only
7
nm
(0.038
eV),
sets
new
record
all
organic
narrowband
luminescent
molecules,
represents
conventional
aromatic
hydrocarbons
(PAHs)
devoid
heteroatoms.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Окт. 31, 2024
Herein,
corannulene-based
quintuple
[6]helicenes
(Q[6]H-1
and
Q[6]H-2)
[7]helicene
(Q[7]H)
were
synthesized
via
penta-fold
Heck
Mallory
reaction.
Notably,
Q[7]H
represents
the
highest
reported
helicene
based
on
corannulene.
X-ray
crystallography
reveals
that
Q[6]H-2
adopts
a
propeller-shaped
conformation
with
well-preserved
corannulene
core,
while
Q[6]H-1
exhibit
quasi-propeller-shaped
conformations.
Upon
heating,
conformer
undergoes
conversion
to
thermodynamically
more
stable
Q[6]H-2,
whereas
remains
unchanged
due
larger
steric
congestion.
Racemization
of
enantiomer
conformational
observed
simultaneously
at
elevated
temperature,
DFT
studies
indicating
racemization
barrier
32.06
kcal
⋅
mol
Precision Chemistry,
Год журнала:
2025,
Номер
3(5), С. 289 - 294
Опубликована: Март 13, 2025
Twisted
nanographenes
(NGs)
are
currently
attracting
a
lot
of
attention
owing
to
their
geometrical
and
electronic
structures
that
differ
substantively
from
conventional
planar
nonplanar
NGs,
while
the
strategic
synthesis
twisted
NGs
is
still
topic
interest
because
products
often
interconvertible
among
unidirectionally,
alternatively,
or
randomly
geometries
otherwise
obtained
as
mixture
them.
Herein,
we
report
conformationally
specific
where
geometry
was
reinforced
by
introducing
1,4-dioxane
rings
at
K-region
central
pyrene
core
bears
large
contortion.
The
were
generated
semi-deprotection,
tetraoxa[4.4.4]propellanes
in
precursor
molecules,
which
confirmed
be
engaged
forming
C–C
bonds
via
Friedel–Crafts
type
mechanism.
contortion
within
causes
narrowed
HOMO–LUMO
gap
on
account
unusual
pz-lobe
overlap
between
+z
−z
sides,
giving
rise
red
emission
with
high
quantum
yield
94%
well
stable
redox
processes
2e–
uptake/release.
Angewandte Chemie International Edition,
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 20, 2024
Abstract
Introduction
of
non‐hexagons
and/or
heteroatoms
allows
for
finely
tuning
the
physicochemical
properties
nanographenes.
Heteroatoms
doping
have
dominated
modulation
nanographenes
with
tunable
band
gap,
rich
electrochemical
activities
and
so
on.
The
pair
non‐hexagons,
instance,
pentagon‐heptagon
pairs,
furnished
aromatic
antiaromatic
characteristics,
open‐shell
In
order
to
meet
growing
demand
versatile
in
materials
science,
research
on
novel
heteroatom
doped
non‐hexagonal
pairs
has
been
aroused
recent
years.
this
review,
we
focus
nitrogen‐doped
paris
including
synthesis,
structure
analysis,
photophysical
properties,
potential
applications
organic
devices.
Angewandte Chemie,
Год журнала:
2024,
Номер
136(43)
Опубликована: Июль 11, 2024
Abstract
The
synthesis
of
fully
fused
π‐conjugated
cycloarenes
embedded
with
nonbenzenoid
aromatics
is
challenging.
In
this
work,
the
first
example
four‐membered
ring‐embedded
cycloarene
(
MF2
)
was
designed
and
synthesized
in
single‐crystal
form
by
macrocyclization
ring
fusion
strategies.
For
comparison,
single
bond‐linked
chiral
macrocycle
MS2
without
two
rings
its
linear‐shaped
polycyclic
benzenoid
monomer
L1
were
also
synthesized.
pronounced
anti‐aromaticity
significantly
adjusts
electronic
structures
photophysical
properties
cycloarene,
resulting
an
enhancement
photoluminescence
quantum
yield
(PLQY)
from
10.66
%
10.74
for
,
respectively,
to
54.05
which
highest
PLQY
among
reported
cycloarenes.
Notably,
owing
anti‐aromatic
that
reduce
structural
displacements,
exhibits
ultra‐narrowband
emission
a
single‐digit
full‐width
at
half‐maximum
(FWHM)
only
7
nm
(0.038
eV),
sets
new
record
all
organic
narrowband
luminescent
molecules,
represents
conventional
aromatic
hydrocarbons
(PAHs)
devoid
heteroatoms.
Angewandte Chemie,
Год журнала:
2024,
Номер
unknown
Опубликована: Окт. 31, 2024
Abstract
Herein,
corannulene‐based
quintuple
[6]helicenes
(
Q[6]H‐1
and
Q[6]H‐2
)
[7]helicene
Q[7]H
were
synthesized
via
penta‐fold
Heck
Mallory
reaction.
Notably,
represents
the
highest
reported
helicene
based
on
corannulene.
X‐ray
crystallography
reveals
that
adopts
a
propeller‐shaped
conformation
with
well‐preserved
corannulene
core,
while
exhibit
quasi‐propeller‐shaped
conformations.
Upon
heating,
conformer
undergoes
conversion
to
thermodynamically
more
stable
,
whereas
remains
unchanged
due
larger
steric
congestion.
Racemization
of
enantiomer
conformational
observed
simultaneously
at
elevated
temperature,
DFT
studies
indicating
racemization
barrier
32.06
kcal
⋅
mol
−1
.
In
contrast,
for
was
calculated
be
45.46
exceptional
chiral
stability.
Surprisingly,
bowl
inversions
conformers
are
somewhat
inhibited
by
helical
blades,
this
not
other
possible
Q[6]H
These
results
first
demonstrated
subtle
variations
can
lead
significant
changes
in
stability
multiple
helicenes.
Due
electron
complementarity,
recognize
fullerenes
both
solution
solid
state,
which
is
rare
instance
co‐crystallization
assembly
between
helicenes
fullerenes.
