Angewandte Chemie,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 18, 2024
Abstract
The
synthesis
and
stabilization
of
heteroatom‐doped
nanocarbon
molecules,
such
as
carbazole‐containing
(super)helicenes,
present
significant
challenges
due
to
the
complexities
involved
in
maintaining
structural
integrity
electronic
functionality.
In
this
study,
we
successfully
synthesized
a
carbazole‐centered
expanded
tris‐hexabenzo[7]helicene
(
1
)
via
facile
FeCl
3
‐mediated
Scholl
coupling
reaction.
exhibits
both
chemical
chiral
stability
demonstrates
fluorescence
at
628
nm
with
quantum
yield
0.40.
Additionally,
enantiomers
display
pronounced
chiroptical
properties,
including
distinct
circular
dichroism
(CD)
signal
spanning
from
300
600
nm.
absorption
dissymmetry
factor
(|
g
abs
|)
is
determined
be
2.98×10
−3
,
while
circularly
polarized
luminescence
brightness
B
CPL
measured
32.50
M
−1
cm
.
Advanced Optical Materials,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 16, 2024
Abstract
Thiahelicenes,
an
important
subclass
of
helicenes,
are
renowned
for
their
pronounced
chiroptical
properties,
particularly
circular
dichroism.
However,
the
exploration
circularly
polarized
luminescence
(CPL)
has
been
hindered
due
to
inherently
weak
fluorescence,
leaving
a
critical
gap
in
development
thiahelicenes
as
efficient
CPL
emitters.
To
address
this
limitation,
novel
strategy
enhancing
by
integrating
thiophene‐containing
units
with
highly
emissive
hexabenzoperylene
(HBP)
core
is
presented.
Two
isomeric
HBP‐cored
double
synthesized,
which
serve
proof
concept.
These
molecules
exhibit
exceptionally
high
fluorescence
quantum
yields
(
Φ
F
=
83%
and
91%),
surpassing
all
previously
reported
thiahelicenes.
Furthermore,
dissymmetry
factors
show
four‐fold
enhancement
compared
parent
HBP,
resulting
remarkable
brightness
up
84.9
M
−1
cm
.
findings
not
only
limitation
but
also
establish
new
pathway
developing
high‐performance
materials.
Molecules,
Год журнала:
2024,
Номер
29(17), С. 3999 - 3999
Опубликована: Авг. 23, 2024
Nanographenes
are
of
increasing
importance
owing
to
their
potential
applications
in
the
photoelectronic
field.
Meanwhile,
recent
studies
have
primarily
focused
on
pure
electronic
spectra
nanographenes,
which
been
found
be
inadequate
for
describing
experimental
that
contain
vibronic
progressions.
In
this
study,
we
effect
transition
a
range
chiral
especially
low-energy
regions
with
distinct
progressions,
using
theoretical
calculations.
All
calculations
were
performed
at
PBE0-D3(BJ)/def2-TZVP
level
theory,
adopting
both
time-dependent
and
time-independent
approaches
Franck-Condon
approximation.
The
resulting
calculated
curves
exhibited
good
alignment
data.
Notably,
nanographenes
incorporating
helicene
units,
Organic Letters,
Год журнала:
2024,
Номер
26(44), С. 9486 - 9491
Опубликована: Окт. 28, 2024
Three
novel
azatwistarenes
5a,
8,
and
13
have
been
synthesized
via
the
Povarov
reaction
fully
characterized.
All
of
enantiomers
were
separated
using
chiral
high-performance
liquid
chromatography,
their
optical
properties
investigated
through
circular
dichroism
circularly
polarized
luminescence
spectra.
In
addition,
such
desired
a
positive
response
to
acid
in
dichloromethane.
Molecules,
Год журнала:
2024,
Номер
29(22), С. 5335 - 5335
Опубликована: Ноя. 13, 2024
Recently,
polycyclic
arenes
with
positive
curvature
have
gained
increasing
significance
in
the
field
of
material
chemistry.
This
study
specifically
explores
inversion
barriers
a
series
positively
curved
circulenes
by
using
five-membered
heterocycles
integrated
into
backbone
primitive
[5]circulenes
and
[6]circulenes.
For
hetero[5]circulenes,
where
one
benzenoid
ring
is
replaced
heterocycle,
exhibit
strong
correlation
rotary
angles
heterocycles,
larger
result
lower
barriers.
Additionally,
aromaticity
circulene
undergoes
significant
reduction
during
process.
As
number
n
rings
increases,
can
be
adjusted,
demonstrating
an
almost
linear
relationship
n.
In
case
hetero[6]circulenes,
molecules
bearing
small
also
show
curvatures.
Furthermore,
we
examine
between
radii
fitted
sphere
for
barriers,
revealing
intriguing
inverse
proportionality
fourth
power
radius
barrier.
We
anticipate
that
this
research
will
offer
fresh
perspective
on
studies
related
to
arenes.
Angewandte Chemie,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 18, 2024
Abstract
The
synthesis
and
stabilization
of
heteroatom‐doped
nanocarbon
molecules,
such
as
carbazole‐containing
(super)helicenes,
present
significant
challenges
due
to
the
complexities
involved
in
maintaining
structural
integrity
electronic
functionality.
In
this
study,
we
successfully
synthesized
a
carbazole‐centered
expanded
tris‐hexabenzo[7]helicene
(
1
)
via
facile
FeCl
3
‐mediated
Scholl
coupling
reaction.
exhibits
both
chemical
chiral
stability
demonstrates
fluorescence
at
628
nm
with
quantum
yield
0.40.
Additionally,
enantiomers
display
pronounced
chiroptical
properties,
including
distinct
circular
dichroism
(CD)
signal
spanning
from
300
600
nm.
absorption
dissymmetry
factor
(|
g
abs
|)
is
determined
be
2.98×10
−3
,
while
circularly
polarized
luminescence
brightness
B
CPL
measured
32.50
M
−1
cm
.
