Inorganic Chemistry,
Journal Year:
2024,
Volume and Issue:
63(42), P. 19872 - 19884
Published: Oct. 8, 2024
Two
new
photoswitchable
dithienylethene
(DTE)-catechol
ligands,
specifically
designed
for
group
13
metal
coordination,
were
synthesized
via
Suzuki
coupling
reactions
from
a
dichloro-DTE
building
block,
each
with
varying
longitudinal
extensions.
The
shorter
DTE-catechol
ligand
did
not
efficiently
assemble
Ga3+
ions;
however,
elongation
phenylene-amide
spacer
enabled
the
successful
formation
of
novel
triply
DTE-functionalized
coordination
[Ga2L3]6–
cage.
This
cage
represents
unique
example
integrating
DTE
photoswitches
main
metals
in
supramolecular
framework.
was
thoroughly
characterized
by
NMR
spectroscopy,
including
DOSY
hydrodynamic
volumetric
analyses,
high-resolution
mass
spectrometry,
computational
DFT,
and
photochemical
analyses.
DFT
studies
highlighted
structural
integrity
dynamic
interplay
within
helicate
mesocate
isomeric
forms
upon
photoswitching.
While
free
ligands
exhibited
all-photonic
reversible
switching
at
up
to
mM
concentrations
alternating
irradiation
365
>495
nm,
demonstrated
these
capabilities
under
dilute
μM
conditions,
albeit
lower
efficiency
fatigue
resistance.
behavior
highlights
intricate
relationship
between
rigid
flexibility
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(30), P. 20720 - 20727
Published: July 18, 2024
Coupling
a
photochemical
reaction
to
thermal
exchange
process
can
drive
the
latter
nonequilibrium
steady
state
(NESS)
under
photoirradiation.
Typically,
systems
use
separate
motifs
for
photoresponse
and
equilibrium-related
processes.
Here,
we
show
that
photoswitchable
imines
fulfill
both
roles
simultaneously,
autonomously
driving
dynamic
covalent
system
into
NESS
continuous
light
irradiation.
We
demonstrate
this
using
transimination
reactions,
where
Chemical Science,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 1, 2025
Using
photoswitchable
molecules
to
manipulate
supramolecular
interactions
under
light
illumination
has
driven
advancements
in
numerous
fields,
allowing
for
the
strategic
alteration
of
molecular
systems.
However,
integrating
moiety
responsible
these
into
photochromic
scaffold
can
be
complex
and
may
hamper
switching
efficiency.
We
thus
explored
a
simple
class
organic
molecules,
namely
thiosemicarbazones,
featuring
both
photoisomerizable
C[double
bond,
length
as
m-dash]N
double
bond
thiourea
capable
hydrogen
bonding.
The
scalable
two-step
synthesis
allowed
us
prepare
23
thiosemicarbazones
systematically
elucidate
their
optical
properties.
Attaching
various
functional
groups,
extended
π-systems,
heterocycles
enabled
fine-tuning
absorption
profiles.
UV
converts
from
stable
E-isomer
metastable
Z-isomer,
exhibiting
negative
positive
T-type
photochromism,
wide
range
thermal
half-lives,
PSS
values
up
92%,
high
fatigue
resistance.
Substituting
with
pyridinyl
group
stabilizes
Z-isomer
via
intramolecular
bonding,
confirmed
by
single-crystal
X-ray
analysis,
transforms
bistable
P-type
photoswitches.
Additionally,
dimerize
or
form
aggregates
through
bonding-a
process
that
turned
off
on
light.
Overall,
offer
tunable
properties,
rendering
them
promising
photoswitch
creating
stimuli-responsive
Organic & Biomolecular Chemistry,
Journal Year:
2025,
Volume and Issue:
23(10), P. 2498 - 2509
Published: Jan. 1, 2025
Dynamic
covalent
macrocycles
offer
the
advantage
of
tunable
ring-opening/ring-closure
and
structural
transformation,
but
their
control
with
precision
remains
a
daunting
task
due
to
labile
nature
reversible
bonds.
Herein
we
demonstrate
precise
formation/scission
varied
sizes
by
contrasting
reactivity,
stability,
degradability
light-active
light-inactive
dynamic
The
incorporation
photoswitchable
non-photoresponsive
aldehyde
sites
into
one
single
dialdehyde
component
afforded
creation
[1
+
1]
type
primary
diamines
suitable
lengths.
manipulation
light
acid/base
stimuli
allowed
on-demand
breaking/remaking
macrocycles,
achieving
interconversion
between
macrocyclic
linear
skeletons.
Moreover,
combination
dialdehyde,
diamines,
secondary
enabled
construction
hetero-type
[2
1
1']
via
enhanced
discrimination
hierarchical
assembly.
Light-induced
kinetic
locking/unlocking
bonds
further
macrocycle-to-macrocycle
conversion
when
needed.
Through
leveraging
controllable
connection/disconnection,
switchable
formation/disintegration
mechanically
interlocked
catenanes
was
accomplished.
results
described
showcase
potential
photoinduced
chemistry
for
preparing
complex
architectures
should
set
stage
molecular
recognition,
assemblies,
synthetic
motors,
responsive
materials.
Journal of the American Chemical Society,
Journal Year:
2025,
Volume and Issue:
unknown
Published: April 22, 2025
Here,
we
report
a
C3-symmetric
tris-azobenzene
cage
1
comprising
azobenzene
cores
and
bis(urea)
units.
This
system
demonstrates
efficient
reversible
photoisomerization
unprecedented
anion-mediated
switching
modes.
Specifically,
the
phosphate
anion
induces
concerted
ZZZ
→
EEE
isomerization
with
prolonged
thermal
relaxation
(t1/2
=
37.5
h
at
298
K).
In
contrast,
bulky
benzene-1,3,5-tricarboxylate
enforces
stepwise
pathway
(ZZZ
EZZ
EEZ
EEE)
rapid
54.4,
44.5,
12.9
min
for
each
step).
study
represents
first
demonstration
of
selective
control
over
multi-azobenzene
switch,
mimicking
biological
adaptability
through
environmental
changes.
Chemical Science,
Journal Year:
2024,
Volume and Issue:
15(9), P. 3290 - 3299
Published: Jan. 1, 2024
Multi-addressable
molecular
switches
with
high
sophistication
are
creating
intensive
interest,
but
challenging
to
control.
Herein,
we
incorporated
ring-chain
dynamic
covalent
sites
into
azoquinoline
scaffolds
for
the
construction
of
multi-responsive
and
multi-state
switching
systems.
The
manipulation
equilibrium
by
acid/base
reactions
primary/secondary
amines
allowed
regulation
E/Z
photoisomerization.
Moreover,
carboxyl
quinoline
motifs
provided
recognition
handles
chelation
metal
ions
turning
off
photoswitching,
otherwise
inaccessible
Z-isomer
complexes
obtained
via
change
stimulation
sequence.
Particularly,
distinct
binding
behaviors
primary
amine
secondary
products
offered
a
facile
way
modulating
reactivity.
As
result,
multiple
control
azoarene
photoswitches
was
accomplished,
including
light,
pH,
ions,
nucleophiles,
interplay
between
diverse
stimuli
further
enabling
addressable
within
reaction
networks.
underlying
structural
mechanistic
insights
were
elucidated,
paving
creation
complex
systems,
assemblies,
intelligent
materials.
Journal of the American Chemical Society,
Journal Year:
2024,
Volume and Issue:
146(46), P. 31892 - 31900
Published: Nov. 5, 2024
The
ubiquitous
ability
of
natural
dynamic
nanostructures
to
adapt
environmental
changes
is
a
highly
desirable
property
for
chemical
systems,
particularly
in
the
development
complex
matter,
molecular
machines,
and
life-like
materials.
Designing
such
systems
challenging
due
generation
mixtures
with
responses
that
are
difficult
predict,
characterize,
diversify.
Here,
we
navigate
between
self-assembled
architectures
using
light
by
operating
an
intrinsic
photoswitchable
building
block
governs
state
system.
When
complementary
units
present,
photoswitch
determines
predominant
architecture,
reversibly
adapting
cage
macrocycles,
including
(otherwise
inaccessible)
higher-energy
assemblies.
Our
study
showcases
this
concept
seven
different
transformations,
offering
unprecedented
degree
control,
diversification,
adaptation
self-selecting
units.
These
findings
could
enable
applications
on-demand
dissipative
macrocycles
based
on
bonds.
We
also
envision
transient
nanostructures,
e.g.,
reticular
polymeric
materials,
being
explored
fine-tuning
nature
unit.
Chemistry - A European Journal,
Journal Year:
2024,
Volume and Issue:
30(33)
Published: April 10, 2024
Click
chemistry
has
reached
its
maturity
as
the
weapon
of
choice
for
irreversible
ligation
molecular
fragments,
with
over
20
years
research
resulting
in
development
or
improvement
highly
efficient
kinetically
controlled
conjugation
reactions.
Nevertheless,
traditional
click
reactions
can
be
disadvantageous
not
only
terms
efficiency
(side
products,
slow
kinetics,
air/water
tolerance,
etc.),
but
also
because
they
completely
avoid
possibility
to
reversibly
produce
and
control
bound/unbound
states.
Recently,
non-covalent
appeared
a
more
alternative,
particular
by
using
host-guest
self-assembled
systems
high
thermodynamic
stability
kinetic
lability.
This
review
discusses
implementation
switches
such
processes,
what
we
have
termed
stimuli-responsive
chemistry,
which
constitutional
states
system
favored
external
stimulation,
complexes.
As
exemplify
handpicked
selected
examples,
these
supramolecular
are
well
suited
human-controlled
conjugation,
coupling
thermodynamically
regulated
processes
appropriate
temporally
resolved
extrinsic
mechanisms,
thus
mimicking
nature
advancing
our
efforts
develop
function-oriented
chemical
synthesis.
A
heteroleptic
[Pd2L2L'2]4+
coordination
cage
containing
a
photoswitchable
azobenzene-derived
ligand
catalyzes
the
Michael
addition
reaction
between
methyl
vinyl
ketone
and
benzoyl
nitromethane
within
its
cavity.
The
correspond-ing
homoleptic
cages
are
catalytically
inactive.
can
be
reversibly
disassembled
reassembled
using
530
nm
light
405
light,
respectively,
allowing
catalysis
to
switched
ON
OFF
at
will.
Angewandte Chemie International Edition,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Nov. 12, 2024
Abstract
We
report
a
light‐responsive
tetrahedral
metal–organic
capsule
that
binds
perrhenate
catalyst,
which
is
released
selectively
upon
irradiation
with
350
nm
light,
turning
on
the
catalytic
reduction
of
organic
carbonyls
by
hydrosilanes.
The
activity
can
be
switched
off
heating
at
75
°C
for
2.5
h,
stimulates
reformation
and
catalyst
re‐encapsulation.
Multiple
on‐off
cycles
were
shown,
clear
relationship
between
product
yield
light
time.
Encapsulation
thus
enables
coupling
light‐responsiveness
to
catalysis
in
manner
might
generalized
other
catalysts
capsules.