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Chiral conjugated materials with curved topologies hold significant promise for advanced optoelectronic applications. Among these, bowl-shaped subphthalocyanine (SubPc) aromatics are particularly noteworthy due to their superb optoelectronic properties and synthetic versatility. Despite their potential, the development and application of inherently chiral SubPcs as functional materials have been hampered by the scalability and feasibility limitations of current high-performance liquid chromatography methods. In this work, we employ axial derivatization with BINOL-based chiral auxiliaries to achieve the optical resolution of C 3 -symmetric SubPcs. This approach allows us to obtain optically active meta and ortho -substituted SubPc derivatives in high yields and enantiomeric excess through straightforward organic chemistry protocols. In addition, we serendipitously observe unprecedented bowl-to-bowl inversion of the SubPc macrocycle upon removal of the derivatizing ligand under specific experimental conditions. These findings represent a significant milestone in the study of chirality in curved aromatics., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Although smartphone ownership among minors has become an important social phenomenon, its impact on children's and adolescents' well-being, as well as the mechanisms by which this might take place are not yet sufficiently well-established. To date, no research has examined the effect of smartphone ownership on the well-being of minors through the consumption of influencer-generated content, nor has it explored the effectiveness of the main prevention strategies employed by parents in this context. To fill those gaps, 800 Spanish minors (50% female) aged from 8 to 16 years old (M = 12.33, SD = 2.38) participated in a correlational study in which the ownership of electronic devices, the consumption of influencer generated content, the parasocial relationship with the influencer, and the most common parental mediation strategies were considered. The results showed a positive association between electronic device ownership and psychological discomfort, problematic usage, and imitation of dangerous behaviors. This association was mediated by the consumption of influencer-generated content and the parasocial relationship established by the minor with the influencer. Regarding preventive strategies, only active mediation was inversely related to poorer well-being indicators, however this positive effect significantly decreased when a smartphone or a similar electronic device was owned by the minor (vs. no owned). These findings contribute to the understanding of how smartphone ownership can affect the well-being of children, emphasizing the need for thoughtful consideration when deciding whether to provide smartphones to minors., (© 2024. The Author(s).)

Two series of metallo-(Zn(II), Mg(II), and Ru(II)) and free-base phthalocyanines (Pcs) with a carboxyl anchoring group and well-established bulky peripheral substituents (either tert-butyl or bulky 2,6-diisopropylphenoxy) were synthesized and tested as sensitizers in dye-sensitized solar cells (DSSCs). The trend of photovoltaic efficiencies (PCEs) for free-base and metallo Pcs followed the order Zn(II)Pc>Mg(II)Pc≫H2Pc ≈ Ru(II)Pc regardless of the peripheral substitution. Higher efficiencies (4.95 versus 3.63 for the Zn(II) derivatives) were achieved with Pcs bearing the bulkier 2,6-diisopropylphenoxy group, indicating a lower aggregation and more suitable HOMO-LUMO levels. Furthermore, these derivatives showed a morelevant influence of the metal on the PCE values (from the highest 4.95 for the Zn(II)Pc to the lowest 0.23 for the Ru(II)Pc. In both series, the best PCEs observed with the Zn(II) derivatives were mainly due to their highest J sc values. The lowest efficiencies found for the free-bases and Ru(II) derivatives were attributed to a mismatch between their LUMO levels and the conduction band of the TiO 2 ,and lower light-harvesting capabilities, respectively. In conclusion, Zn(II) derivatives are still the best Pc candidates to use as sensitizers in molecular photovoltaics., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Large π-conjugated systems are key in the area of molecular materials. Herein, we prepare via Au I -catalyzed cyclization a series of fully π-conjugated anthracene-fused oligo-BODIPYs. Their structural and optoelectronic properties were studied by several techniques, ranging from X-ray, UV/Vis, and cyclic voltammetry to transient absorption spectroscopy. As a complement, their electronic structures were explored by means of Density Functional Theory (DFT) calculations. Depending on the size and shape of the π-conjugated skeleton, unique features-such as face-to-face supramolecular organization, NIR absorption and fluorescence as well as strong electron accepting character-were noted. All in all, the aforementioned features render them valuable for technological applications., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Half a century after the synthesis of the first subporphyrinoid, the study of tripyrrole and trisoindole porphyrin analogues constitutes a fervent and rapidly expanding research area. The outstanding structural, electronic and optical features of these cone-shaped aromatic macrocycles render them attractive candidates for a wide variety of applications, ranging from optoelectronics to biomedicine. To tune their properties and exploit their functionalities, the development of novel methodologies for the synthesis and post-functionalization of these contracted porphyrinoids, as well as a deep understanding of their supramolecular organization and their implementation into multicomponent systems of increasing complexity are of paramount importance. Herein, a review of the most recent advances in the fundamentals and applications of subporphyrinoids is presented, which comprehensively cover the last decade of discoveries. The final aim is to highlight the chemical versatility and intriguing physicochemical features of subporphyrinoids, while providing an updated overview of their most promising applications.

Here we report gold(i)-catalyzed cycloisomerization as a new powerful synthetic tool for the preparation of π-extended BODIPY derivatives. The catalytic system PPh F 3 AuCl/AgSbF 6 enables the synthesis of [ b ]-[2,1]naphtho-fused-BODIPYs ( 2a-2c ) under mild conditions, in excellent yields and short reaction times. The reaction is totally regioselective to the 6- endo -dig product and for the α-position of the BODIPY, which is both the kinetically and thermodynamically favored pathway, as supported by the free energy profile calculated by means of Density Functional Theory (DFT). Moreover, this methodology also allows the synthesis of two new families of [ b ]-aryl-fused-BODIPYs, namely, [3,4]phenanthro- ( 2e and 2f ) and [1,2]naphtho-fused ( 2g ) BODIPYs. Their molecular and electronic structures were established by NMR and UV-vis spectroscopies as well as single-crystal X-ray diffraction analysis. As can be noted from the X-ray structures, 2a , 2e and 2g present interesting structural differences at both the molecular and packing level. Interestingly, despite being isomers, the UV/vis spectra of 2a and 2g revealed significant differences in their electronic structures. The origin of this finding was studied by Time-Dependent DFT calculations. Calculated DFT Nuclear Independent Chemical Shift (NICS(0)) values also supported the different electronic structures of 2a and 2g ., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

A family of inherently chiral nonplanar aromatic chromophores, comprising Subphthalocyanines bearing fluorenone-fused units (SubFcs), have been prepared by an innovative one-pot synthesis, which relies on the standard cross-cyclotrimerization of phthalonitriles followed by intramolecular Friedel-Crafts acylation. Their Q-band absorption experiences a ca. 20 nm red shift per fused fluorenone as a consequence of the enlarged conjugated π-system.

A series of peripherally dicyano-, tricyano-, and tetracyano-substituted subphthalocyanines (SubPcs) have been prepared through microwave-assisted, palladium-mediated cyanation of iodinated precursors. The introduction of π-accepting cyano groups in the macrocycle clearly influences its electronic and redox properties, which are dependent on the number and relative position of these substituents. Additional functionalization of the periphery of SubPcs with electron-donating or -withdrawing groups allows for a further fine-tuning of their features, leading to intensely absorbing, strongly electron-accepting panchromatic dyes with low-lying LUMO energy levels. Flash-photolysis time-resolved microwave conductivity measurements on vapor-deposited films demonstrate that some of these novel SubPc derivatives display remarkable intrinsic charge-carrier mobilities that are comparable to or larger than those of other known well-performing acceptor SubPcs; thus confirming their potential as n-type organic semiconductors for application in the fabrication of photovoltaic devices., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Four hexachlorosubphthalocyanines SubPcCl 6 -X bearing different axial substituents (X) have been synthesized for use as novel electron acceptors in solution-processed bulk-heterojunction organic solar cells. Subphthalocyanines are aromatic chromophoric molecules with cone-shaped structure, good solution processability, intense optical absorption in the visible spectral region, appropriate electron mobilities, and tunable energy levels. Solar cells with subphthalocyanines as the electron acceptor and PTB7-Th as the electron donor exhibit a power conversion efficiency up to 4 % and an external quantum efficiency approaching 60 % due to significant contributions from both the electron donor and the electron acceptor to the photocurrent, indicating a promising prospect of non-fullerene acceptors based on subphthalocyanines and structurally related systems., (© 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

To date β-aryloxy-substituted designs have led to the best results in phthalocyanine-sensitized solar cells (Pc-SCs) because of their low aggregation properties. By incorporating the bulky semiflexible 2,6-diphenylphenoxy group at three α-positions of the Pc, different regioisomers were separated by column chromatography and their photovoltaic performance was thoroughly studied. Efficiencies in the range of 1.9-4.1 % were found, thus demonstrating the importance of the steric interaction between the substituents and the semiconductor surface, also in the case of bulky semiflexible substituents. It was discovered that regioisomers which presented greater steric hindrance around the anchoring group, had lower adsorption densities, and, consequently, lower short-circuit photocurrents (J sc ) and efficiencies., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Phthalocyanines (Pcs) are used as sensitizers in dye-sensitized solar cells (DSSCs) because of their stability and intense absorption in the red and near-IR regions. Impressive progress has been made in photovoltaic efficiencies by introduction of bulky peripheral substituents to help suppress macrocycle aggregation. To reach benchmark efficiencies reported for other related dyes, new designs need to be explored. Single carboxy-ZnPc regioisomers substituted at the non-peripheral positions by rigid aryl groups have now been studied, which has shed light on the influence of steric hindrance and/or orientation of the substituent around the anchoring group on the photovoltaic response. The regioisomer bearing the aryl group far away from the anchoring group produces a more effective sensitization of the TiO2 films and higher short-circuit photocurrent density (Jsc). Taking advantage of the good photovoltaic performance in the near-IR region of this ZnPc, it was combined with another appropriate dye for panchromatic sensitization of the mesoporous photoelectrode and an increase of the overall device efficiency., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Unsymmetrical subphthalocyanine fused dimers have been prepared from appropriate ortho -dinitrile SubPc precursors. In particular, either electron-donating or electron-accepting substituents have been introduced on each SubPc constituent unit, resulting in unprecedented push-pull π-extended curved aromatic macrocycles. From fluorescence experiments in solvents of different polarity we conclude a dual fluorescence, namely a delocalized singlet excited state (1.73 eV) and a polarized charge transfer state (<1.7 eV). Pump probe experiments corroborate the dual nature of the fluorescence. On one hand, the delocalized singlet excited state gives rise to a several nanosecond lasting intersystem crossing yielding the corresponding triplet excited state. On the other hand, the polarized charge transfer state deactivates within a few picosesonds. Visualization of the charge transfer state was accomplished by means of molecular modeling with a slight polarization of the HOMO towards the electron donor and of the LUMO towards the electron acceptor.

A new design of nonaggregated zinc(II) carboxyphthalocyanines with potential application in dye-sensitized solar cells has been developed. It is based on the introduction of bulky and rigid aryl groups at three α positions of the macrocycle. The synthesis has been carried out following a convergent route in which the bulky aryl groups are introduced by a Suzuki-Miyaura cross-coupling reaction on a preformed triiodophthalocyanine derivative. Two regioisomers of this α-triaryl-β-carboxyphthalocyanine could be isolated by column chromatography.

A series of subphthalocyanines (SubPcs) bearing a carboxylic acid group either at the peripheral or axial position have been designed and synthesized to investigate the influence of the COOH group positions on the dye-sensitized solar cell (DSSC) performance. The DSSC devices based on SubPcs with axially substituted carboxylic acid groups showed low photovoltaic performance, whereas peripherally substituted one exhibited higher power conversion efficiency owing to improved injection from LUMO of SubPcs to the TiO2 conduction band., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Zinc(II) phthalocyanine dyes that contain triarylamine-terminated bisthiophene and hexylbisthiophene groups have been synthesized by a convergent approach by using carboxytriiodo-ZnPc as a precursor. Further transformation of the iodo groups by a Pd-catalyzed reaction allowed easy preparation of further extended π-conjugated carboxy-ZnPcs. These dyes have been used as sensitizers in dye-sensitized solar cells, which exhibit a panchromatic response and moderate overall efficiencies., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel supramolecular electron donor-acceptor hybrid (2·1) and an electron donor-acceptor conjugate (3), both exhibiting a remarkably shifted Q band in the NIR region of the solar spectrum, were prepared. Irradiation of the supramolecular ensemble 2·1 within the visible range leads to a nanosecond lived radical-ion pair state Zn-azulenocyanine˙(+)-C(60)˙(-)., (This journal is © The Royal Society of Chemistry 2012)

We report on immobilizing H(2)/Zn-porphyrin-Zn-phthalocyanine conjugates onto single wall carbon nanotubes and by using the excellent stability of the resulting suspensions we were able to demonstrate for the first time the sequence of energy transfer-electron transfer in SWNT donor-acceptor conjugates.

The synthesis of stopcocks based on zinc phthalocyanine for selective adsorption at the channel entrances of zeolite L is reported. The introduction of either an inert SiMe₃ moiety, an imidazolium cation or a reactive isothiocyanate (NCS) group allows attachment to the channel entrances of zeolite L through van der Waals interactions, electrostatic interactions, or covalent binding, respectively. Stopcocks that rely on van-der-Waals-driven adsorption require careful selection of the solvent used for the deposition onto the zeolite surface to avoid a nonspecific distribution of the molecules. Regarding the design of photonic antenna systems, a stopcock with a cationic tail was found to be the most convenient, based on the observation that efficient energy transfer from molecules located in the zeolite nanochannels is more readily obtained than in the other cases.

The field of organic photovoltaics (OPV) represents one of the most promising technological areas. Porphyrins and phthalocyanines are perfectly suited for their integration in light energy conversion systems. These colored macrocycles exhibit very attractive physical properties, particularly very high extinction coefficients in the visible and near IR regions, where the maximum of the solar photon flux occurs, that is necessary for efficient photon harvesting, besides a rich redox chemistry, as well as photoinduced electron transfer and semiconducting capabilities.

Complementary experiments, that is, femtosecond up-conversion fluorescence, conventional fluorescence lifetime measurements, and transient absorption measurements, imply efficient porphyrin-to-phthalocyanine energy transfer phenomena in NH-connected porphyrin/phthalocyanine conjugates.

A series of dithiolane-substituted subphthalocyanines have been synthesized that can form self-assembled monolayers on gold surfaces, as confirmed by diverse characterization techniques.

A supramolecular phthalocyanine-squaraine ensemble which exhibits a large coverage of the solar spectrum from 850 to 250 nm has been prepared and characterized both photophysically and in bulk heterojunction solar cells.

Within the present work, two series of novel ruthenium(II) phthalocyanine (RuPc) complexes with one [RuPcCOPy-nT] or two [RuPc(Py-nT)(2)] dendritic oligothiophene (DOT) ligands in the axial positions are reported. The ability of Ru(II) for axial coordination in RuPcs allowed the attachment of the Pc through the metal site to the DOT-ligands bearing pyridine at the core position of the dendrons. These extended pyridine functionalized conjugated DOT-ligands (Py-nT) were chosen to cover the spectral window between 380 and 550 nm, where the RuPc does not exhibit a strong absorption, in order to improve the light-absorption of these complexes and hence enhance the efficiency of the corresponding solar cells. Good efficiencies of up to 1.6% have been achieved when blended together with a fullerene acceptor in solution-processed photovoltaic devices, providing by far the best phthalocyanine-based bulk heterojunction solar cells reported to-date.

We report the first phthalocyanine-based stopcock for selective adsorption to the channel entrances of zeolite L and realisation of a new electronic dipole moment coupling situation.

The use of blends in which a mesogen induces mesomorphism into a non-mesogenic compound has made possible the self-organization of phthalocyanine--[60]fullerene (Pc-C60) dyads into liquid crystals. Pc-C60 dyads 1, 2, or 3, in which two photoactive units are brought together by a phenylenevinylene spacer, have been synthesized through a Heck reaction that links 4-vinylbenzaldehyde to a monoiodophthalocyanine precursor, followed by standard cycloaddition of azomethine ylides--generated from the formylPc derivative and N-methylglycine--to one of the double bonds of C60. The mesomorphic and thermal properties of different mixtures formed by the liquid-crystalline phthalocyanine 4 and dyads 1, 2, or 3 were examined using polarizing optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). DSC diagrams of the blends show clear transitions from the crystalline state to a mesophase, and the measured structural parameters obtained from the powder diffraction experiments are consistent with a discotic hexagonal columnar (Col h) structure. Considering that segregation in domains of separated molecules of Pc-C60 dyad and phthalocyanine 4 would preclude mesomorphism due to the mismatch in the column diameter and to the lack of mesogenic character of the pure dyads, a predominance of alternating stacking is proposed. Additionally, the observed decrease in the calculated density of the blend mesophases relative to the mesophase of pure compound 4 is important evidence in this direction.

[structure: see text] Two types of covalently NH-linked porphyrin-phthalocyanine dyads, connected either through the meso phenyl group or the beta-pyrrolic position of the porphyrin, have been synthesized following statistical condensation methodologies for phthalocyanine preparation and palladium-catalyzed amination methods. Photophysical studies have revealed that energy transfer from the porphyrin to the phthalocyanine prevails regardless of linkage.

New donor-acceptor materials based on a polynorbornene framework to which both phthalocyanine and C60 electroactive pendant units are randomly attached have been prepared in good yield by ring-opening-metathesis polymerization (ROMP) in the presence of a Grubbs catalyst. A structurally related phthalocyanine homopolymer was also synthesized for comparison. A remarkable fluorescence quenching was observed in the homopolymer and accounts for PcPc interactions along the polymeric framework. As expected, the fluorescence quenching increases in the case of the polynorbornenes containing both Pc and C60 units owing to photoinduced electron transfer, which was further confirmed by transient absorption spectroscopy. Finally, preliminary solar cell devices made of one of the copolymers were constructed.

A novel ZnPc-C60 dyad (3), in which two photoactive units are brought together by a phenylenevinylene spacer has been synthesized. The synthetic strategy en route toward 3 involves a Heck reaction to attach 4-vinylbenzaldehyde to a monoiodophthalocyanine precursor, followed by standard cycloaddition of azomethine ylides (generated from the formylPc derivative and N-methylglycine) to one of the double bonds of C60. Electrochemical studies reveal that in 3 the ZnPc is about 39 mV more difficult to oxidize than in the corresponding ZnPc reference, which points to appreciable electronic communication between ZnPc and C60 in the ground state. In the excited state, photoexcitation leads to the formation of a charge-separated ZnPc*+-C60*- state, for which a lifetime of 130 ns was determined in THF. Hetero-association between complementary Pcs (1 and 2 or 3 and 2), which carry different peripheral functionalities (i.e., either electron-donating alkoxy groups or electron-deficient alkylsulfonyl chains) was assessed by different techniques. They provided evidence for donor-acceptor 1:1 complex formation with a stability constant of ca. 10(5) M(-1) in CHCl3. Interestingly, hetero-association of ZnPc-C60 dyad 3 with an electron-deficient PdPc (2) allowed the construction of supramolecular triads, in which a substantial stabilization of the radical pair is seen relative to that of the covalently linked dyad ZnPc-C60 (3).

A novel donor-acceptor bisphthalocyanine (bis-Pc, 1) in which two different Pc units (Zn(II)-Pc and Ni(II)-Pc) are linked via vinylene spacers to the pseudopara positions of a central [2.2]paracyclophane moiety is described. The synthesis of 1 is achieved by two successive Heck reactions of pseudopara-divinyl[2.2]paracyclophane 9 with, sequentially, a zinc(II)- and a nickel(II)-iodophthalocyanine (4 and 5, respectively). The self-assembly ability of 1, which is the result of the complementary donor-acceptor character of its phthalocyanine units, has been assessed by a variety of techniques. It is revealed that 1 forms one-dimensional aggregates of nanometer-sized dimension, whereas equimolar mixtures of the donor and acceptor Pc subunits 2 and 3, although strongly interacting, do not give large arrays. The aggregates of 1 represent a novel type of supramolecular polymers based mainly upon donor-acceptor interactions.

Novel zinc phthalocyanine (ZnPc)/fullerene ligand (L) ensembles are assembled following simple biomimetic principles, which upon photoexcitation give rise to intra complex electron transfer quenching of the 1*ZnPc fluorescence.

Three [2]catenanes and three [3]catenanes incorporating one or two pi-electron-rich macrocyclic polyethers and one pi-electron-deficient polycationic cyclophane have been synthesized in yields ranging from 4 to 38%. The pi-electron-rich macrocyclic components possess either two 1,4-dioxybenzene or two 1.5-dioxynaphthalene recognition sites. The pi-electron-deficient cyclophane components incorporate two bipyridinium and either one or two dialkylammonium recognition sites. The template-directed syntheses of these catenanes rely on i) pi...pi stacking interactions between the dioxyarene and bipyridinium recognition sites, ii) C-H...O hydrogen bonds between some of the bipyridinium hydrogen atoms and some of the polyether oxygen atoms, and iii) C-H...pi interactions between some of the dioxyarene hydrogen atoms and the aromatic spacers separating the bipyridinium units. The six catenanes were characterized by mass spectrometry and by both 1H and 13C NMR spectroscopy. The absorption spectra and the electrochemical properties of the catenanes have been investigated and compared with those exhibited by the component macrocycles and by related known catenanes. Broad and weak absorption bands in the visible region, originating from charge-transfer (CT) interactions between electron-donor and electron-acceptor units, have been observed. Such charge-transfer interactions are responsible for the quenching of the potentially fluorescent excited states of the aromatic units of the macrocyclic polyether components. The redox behavior of these novel compounds has been investigated and correlations among the observed redox potentials are illustrated and discussed. The catenanes undergo co-conformational switching upon one-electron reduction of the two bipyridinium units. One of them--in its reduced form--can be also switched by acid/base inputs and exhibits AND logic behavior. The co-conformational rearrangements induced by the redox and acid/base stimulations lend themselves to exploitation in the development of molecular-level machines and logic gates.