Two-way photoswitching norbornadiene derivatives for solar energy storage.

Molecular photoswitches of norbornadiene (NBD) derivatives have been effectively applied in molecular solar-thermal energy storage (MOST) by photoisomerization of NBD to a quadricyclane (QC) state. However, a challenge of the NBD-based MOST system is the lack of a reversible two-way photoswitching process, limiting conversion from QC to thermal and catalytic methods. Here we design a series of NBD derivatives with a combination of acceptor and donor units to achieve two-way photoswitching, which can optically release energy by back-conversion from QC to NBD.

Norbornadiene-Quadricyclane Photoswitches with Enhanced Solar Spectrum Match.

Herein, we report monomeric and dimeric norbornadiene-quadricyclane molecular photoswitch systems intended for molecular solar thermal applications. A series of six new norbornadiene derivatives conjugated with benzothiadiazole as the acceptor unit and dithiafulvene as the donor unit were synthesized and fully characterized. The photoswitches were evaluated by experimentally and theoretically measuring optical absorption profiles and thermal conversion of quadricyclane to norbornadiene.

Pyrene Functionalized Norbornadiene-Quadricyclane Fluorescent Photoswitches: Characterization of their Spectral Properties and Application in Imaging of Amyloid Beta Plaques.

This study presents the synthesis and characterization of two fluorescent norbornadiene (NBD) photoswitches, each incorporating two conjugated pyrene units. Expanding on the limited repertoire of reported photoswitchable fluorescent NBDs, we explore their properties with a focus on applications in bioimaging of amyloid beta (Aβ) plaques. While the fluorescence emission of the NBD decreases upon photoisomerization, aligning with what has been previously reported, for the first time we observed luminescence after irradiation of the quadricyclane (QC) isomer.

Synthesis and Characterization of Carbon-Based Heterogeneous Catalysts for Energy Release of Molecular Solar Thermal Energy Storage Materials.

Molecular solar thermal energy storage (MOST) systems are rapidly becoming a feasible alternative to energy storage and net-zero carbon emission heating. MOST systems involve a single photoisomerization pair that incorporates light absorption, storage, and heat release processes in one recurring cycle. Despite significant recent advancements in the field, the catalytic back-reaction from MOST systems remains relatively unexplored.

Synthesis of Dioxa-1,7-naphthicorrole and Its Oxidized Porphyrinoid as a Potential Built-In Linker for Biomolecules.

The first aromatic benzicorrole termed naphthicorrole was synthesized with a carbon donor containing more than six members. Its oxidized (enedione-embedded) porphyrinoid was also obtained using different meso-aryl substitutions under sequential oxidation conditions. The resulting enedione motif of the nonaromatic porphyrinoid was regioselective to the C2 position for S or N nucleophiles.

-(2-Thienyl)vinylarene as an Alternative Synthetic Motif for Porphyrinoids: -Arene-Connected Porphyrinoids.

-Arene-connected porphyrinoids were synthesized with -(2-thienyl)vinylarene motif as a new building block for porphyrinoids. This motif can replace meso-aryl-substituted dipyrromethene and serve as a command key arranging -connectivity of porphyrinoid. While (benzene version) is very weak, (pyridine version) shows a substantial amount of diatropic ring current due to reduced steric hindrance (without H23) and rigidified became more aromatic than .

Carbaporphyrin Dimers That Bear a Rigid Naphthalene Motif as an Internal Strap.

The first fully connected aromatic carbaporphyrin dimer () and its bis-Pd complex () that bear a rigid naphthalene motif as an internal strap were synthesized. These dimers consisted of two aromatic carbaporphyrins that shared a naphthalene motif. The π-electron conjugation of the obtained macrocycles was proposed to have two separated local 22 π-electron pathways and a 34 π-electron pathway.

Synthetic Anion Transporters as Endoplasmic Reticulum (ER) Stress Inducers.

Cl-ion transporters (-) were synthesized based on the binding motifs of prodigiosin. Transporter clearly displays Cl-ion transportation activity across both model and live cell membranes. Furthermore, can disrupt Ca homeostasis and increase the intracellular concentration of Ca in the DLD-1 cell.

Bond Rotation in an Aromatic Carbaporphyrin: Allyliporphyrin.

Allyliporphyrin is a carbaporphyrin that has replaced one pyrrole with an allyl group. Dynamic behavior (bond rotation) was observed by variable temperature H NMR and 2D-NOESY NMR spectroscopy and theoretically examined by DFT calculations. These studies revealed that well-defined bond rotation was first observed in the limited space of the carbaporphyrin from 2 through cis-2 and the calculated rotational barrier was low enough, with the relative energy level of cis-2 only 0.

Synthesis of a Phlorin from a Meso-Fused Anthriporphyrin by a Diels-Alder Strategy.

An anthracene-containing meso-fused carbaporphyrin, which has extended π-conjugation pathways as compared to the corresponding naphthalene-containing carbaporphyrin, has been synthesized. The weak global aromaticity of the anthriporphyrin also allowed its use as the diene for a Diels-Alder reaction with dimethyl acetylenedicarboxylate (DMAD). The resulting phlorin contains an interesting bicyclic structure.

2-(Naphthalen-1-yl)thiophene as a New Motif for Porphyrinoids: Meso-Fused Carbaporphyrin.

The first synthesis of meso-fused carbaporphyrin via a premodification method was accomplished by substituting two pyrrole moieties and one meso-carbon with 2-(naphthalen-1-yl)thiophene. The obtained global π-conjugation pathway of the macrocycle noticeably disturbs the 10π local aromaticity of naphthalene, and its aromatic nature was supported by NMR spectroscopy together with nucleus-independent chemical shift, anisotropy of the induced current density, and harmonic oscillator stabilization energy calculations. In addition, the meso-fused carbaporphyrin also allowed the formation of a square planar Pd(II) complex.