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Building supramolecular helical structures is a challenge due to difficulties in the design and control of competitive noncovalent forces.

A novel phthalocyanine-based benzimidazole linked conjugated covalent organic polymer (NiPc-COP1) has been synthesized with multiple randomly ordered crystalline morphologies.

In this study, the efficiency of halogen⋯halogen interactions to control supramolecular assemblies of boron dipyrromethene (BODIPY) (B1–B5) derivatives was explored.

Here, we present the first example of sp3 hybridized carbon centered (Csp3) tetrel bonding mediated 3D BODIPY assembly via the exceptional synergy of Csp3⋯N and Csp3⋯F pair interactions. The carbon tetrel bond interaction energies of Csp3⋯N and Csp3⋯F are amplified significantly as the size of the 1D chain grows from dimer to tetramer BODIPY units.

In this study, the efficiency of halogen bonding strategies to control over the supramolecular assemblies of boron dipyrromethene (BODIPY) (B-1, B-2, and B-3) derivatives was explored. BODIPY cores were decorated with iodine (XB donor) and pyridine (XB acceptor) groups to promote halogen bonding formations. Single crystal X-ray diffraction analysis revealed the formation of I⋯X (N, F) XB, which led to the impressive halogen-bonded supramolecular self-assembly of 2-D layers (B-1), 1-D ladder-like chains (B-2), and helical assembly (B-3). The molecular electrostatic potential (MEP) showed the presence of σ holes on the outer tip of the iodine for all compounds. The SAPT analysis clarified the decomposition of interaction energies. The results revealed that the electrostatic forces have the largest contributions to XB in dimers of B-2, whereas dispersion components are the major source of XB interactions in dimers of B-1 and B-3. The additional AIM theory analysis showed the bond critical points (BCPs) between I⋯N, F which also confirm the presence of halogen bonding in B-1, B-2, and B-3.

A one‐dimensional nanotubular metal–organic framework (MOF) [Ni(Cu‐H4TPPA)]⋅2 (CH3)2NH2 + (H8TPPA=5,10,15,20‐tetrakis[p‐phenylphosphonic acid] porphyrin) constructed by using the arylphosphonic acid H8TPPA is reported. The structure of this MOF, known as GTUB‐4, was solved by using single‐crystal X‐ray diffraction and its geometric accessible surface area was calculated to be 1102 m2 g−1, making it the phosphonate MOF with the highest reported surface area. Due to the extended conjugation of its porphyrin core, GTUB‐4 possesses narrow indirect and direct bandgaps (1.9 eV and 2.16 eV, respectively) in the semiconductor regime. Thermogravimetric analysis suggests that GTUB‐4 is thermally stable up to 400 °C. Owing to its high surface area, low bandgap, and high thermal stability, GTUB‐4 could find applications as electrodes in supercapacitors., A 1D nanotubular MOF, GTUB‐4, was constructed by using the highly conjugated arylphosphonic acid H8‐TPPA. The structure of this metal–organic framework (MOF) was solved by using single‐crystal X‐ray. GTUB‐4 is characterized by high surface area and, due to the extended conjugation of its porphyrin core, possesses narrow indirect and direct bandgaps in the semiconductor regime. Owing to its high surface area, low band gap, and high thermal stability, GTUB‐4 could find applications as electrode material in supercapacitors.

Herein, we report a semiconductive, proton-conductive, microporous hydrogen-bonded organic framework (HOF) derived from phenylphosphonic acid and 5,10,15,20‐tetrakis[p‐phenylphosphonic acid] porphyrin (GTUB5). The structure of GTUB5 was characterized using single crystal X-ray diffraction. A narrow band gap of 1.56 eV was extracted from a UV-Vis spectrum of pure GTUB5 crystals, in excellent agreement with the 1.65 eV band gap obtained from DFT calculations. The same band gap was also measured for GTUB5 in DMSO. The proton conductivity of GTUB5 was measured to be 3.00 × 10−6 S cm−1 at 75 °C and 75% relative humidity. The surface area was estimated to be 422 m2 g−1 from grand canonical Monte Carlo simulations. XRD showed that GTUB5 is thermally stable under relative humidities of up to 90% at 90 °C. These findings pave the way for a new family of organic, microporous, and semiconducting materials with high surface areas and high thermal stabilities., Research in hydrogen-bonded organic frameworks (HOFs) has gained interest in recent years due to their facile design and synthesis but no semiconducting HOF has been reported to date. Here the authors report a thermally stable and proton-conductive organic semiconductor based on a porphyrin HOF.

Novel phthalocyanine-based benzimidazole linked conjugated covalent organic polymer (NiPc-COP1) have been synthesized with multiple randomly ordered crystalline morphology. This unique alignment leads to significantly enhanced panchromatic light-absorption capability, thus high photoconductivity with high photoresponce speed.

Organic luminescent compounds with high emission properties play a crucial role in fluorescence labelling and optoelectronic devices. In this work, we prepared three water soluble BODIPY derivatives (B-4, B-5, and B-6) which are weakly fluorescent due to non-radiative relaxation pathways (charge transfer: CT or heavy atom effect). However, CB[7] significantly improves BODIPY fluorescence by similar to 10 fold for B-4, and by similar to 3 fold for B-5. The (TD)DFT analyses suggest that for B-4 and B-5, the CT state is blue-shifted as a result of the external binding of CB[7] near the pyridinium groups. This effect favoured a radiative decay through a locally-excited (LE) pi ->pi* transition state of BODIPYs resulting in a CB[7]-induced emission increase in solution (and in the solid state), without compromising singlet-to-triplet intersystem crossing (ISC). The improved emission of the BODIPY center dot CB[7] complexes was used for the fluorescence imaging of U87 cells illustrating the relevance of this approach. These results suggest that BODIPY center dot CB[7] complexes could be used as theragnostic agents by combining fluorescence imaging and treatment by photodynamic therapy.

Here, we present viologen-porphyrin based ionic covalent organic polymers (H2-ICOP and Zn-ICOP) with multiple CO2-philic sites. The specific surface areas of H2-ICOP and Zn-ICOP were found to be 9 m(2) g(-1) and 20 m(2) g(-1), respectively. CO2 uptake analyses reveal that H2-ICOP exhibits very high CO2 capture uptake (62.9 mg g(-1)), which is one of the highest values among previously reported ICOPs. The results indicate very efficient non-covalent interactions between H2-ICOP and CO2. The possible non-covalent interactions of hydrogen (O-CO2...H-N), tetrel (C-CO2...N, C-CO2...Cl-), pnicogen (O-CO2...N+), and spodium bonds (O-CO2...Zn) between CO2 and H2-ICOP and Zn-ICOP are investigated via symmetry adapted perturbation theory (SAPT) analysis and electrostatic potential maps (MEP). The strength of non-covalent interactions in H2-ICOP and Zn-ICOP is decreasing in the following order Delta E-C...(N) > Delta E-C...(-)(Cl) > Delta E-O...(+)(N) and Delta E-Zn...(O) > Delta E-C...(-)(Cl) > Delta E-C...(N) > Delta E-O...(+)(N), respectively. The major CO2 uptake contribution comes from C-CO2...N tetrel bonding (-22.02 kJ mol(-1)) interactions for H2-ICOP, whereas O-CO2...Zn spodium bonding (-21.065 kJ mol(-1)) interactions for Zn-ICOP. H2-ICOP has more CO2-philic moieties with powerful non-covalent interactions compared to Zn-ICOP, which is in good agreement with the experimental results. Furthermore, the CO2 catalytic conversion performances of Zn-ICOP and H2-ICOP gave good yields of 83% and 54%, respectively. Surprisingly, Zn-ICOP, despite having significantly lower CO2 uptake capacity, displayed better catalytic activity than H2-ICOP, owing to a higher number of counter anions (Cl-) on its surface, which shows the crucial role of the counter anion (Cl-) in the mechanism of this catalytic reaction., Science Academy, Young Scientist Award (BAGEP), The authors thank the TUBITAK ULAKBIM High Performance and Grid Computing Center (TRUBA resources), Turkey, for computational facilities. Y. Zorlu acknowledges financial support from The Science Academy, Young Scientist Award (BAGEP).

Inverse electron demand Diels-Alder (IEDDA) reaction has been employed as a powerful ligation in several fields. In the current work, a synthetic approach relying on IEDDA reaction is developed for preparation of a porphyrin based covalent organic polymer (PoTz-COP). A tetra-norbornene functional porphyrin is chosen as the core and a bis-tetrazine as the linker. The PoTz-COP is readily formed by just mixing the components without a catalyst and under mild conditions. Chemical structure, morphology (XRD, SEM-EDX), porosity (BET), thermal stability (TGA), optical and gas sorption (CO2 uptake) and selectivity (CO2/N2) properties via Myers and Prausnitz's ideal adsorbed solution theory (IAST) are investigated. PoTz-COP shows remarkably high adsorption selectivity of CO2 over N2 as found 80, 42, and 47 at 50/50 ratio; 84, 39 and 40 at 15/85 ratio; and 84, 39 and 38 at 05/95 ratio at temperatures of 273 K, 298 K and 320 K at 1.1 bar pressure respectively. The optical band gap is determined relatively narrow as 1.66 eV.

Herein, the design and synthesis of a highly photoluminescent and electrically conductive metal–organic framework [Zn{Cu‐p‐H6TPPA}]⋅2 [(CH3)2NH] (designated as GTUB3), which is constructed using the 5,10,15,20‐tetrakis [p‐phenylphosphonic acid] porphyrin (p‐H8TPPA) organic linker, is reported. The bandgap of GTUB3 is measured to be 1.45 and 1.48 eV using diffuse reflectance spectroscopy and photoluminescence (PL) spectroscopy, respectively. The PL decay measurement yields a charge carrier lifetime of 40.6 ns. Impedance and DC measurements yield average electrical conductivities of 0.03 and 4 S m−1, respectively, making GTUB3 a rare example of an electrically conductive 3D metal–organic framework. Thermogravimetric analysis reveals that the organic components of GTUB3 are stable up to 400 °C. Finally, its specific surface area and pore volume are calculated to be 622 m2 g−1 and 0.43 cm3 g−1, respectively, using grand canonical Monte Carlo. Owing to its porosity and high electrical conductivity, GTUB3 may be used as a low‐cost electrode material in next generation of supercapacitors, while its low bandgap and high photoluminescence make it a promising material for optoelectronic applications.

Hydroethidine (HE) and hydropropidine ($$\hbox {HPr}^{+}$$ HPr + ) are fluorogenic probes used for the detection of the intra- and extracellular superoxide radical anion ($$\hbox {O}_{ {2}}^{\bullet -}$$ O 2 ∙ - ). In this study, we provide evidence that HE and $$\hbox {HPr}^{+}$$ HPr + react rapidly with the biologically relevant radicals, including the hydroxyl radical, peroxyl radicals, the trioxidocarbonate radical anion, nitrogen dioxide, and the glutathionyl radical, via one-electron oxidation, forming the corresponding radical cations. At physiological pH, the radical cations of the probes react rapidly with $$\hbox {O}_{ {2}}^{\bullet -}$$ O 2 ∙ - , leading to the specific 2-hydroxylated cationic products. We determined the rate constants of the reaction between $$\hbox {O}_{ {2}}^{\bullet -}$$ O 2 ∙ - and the radical cations of the probes. We also synthesized N-methylated analogs of $$\hbox {HPr}^{+}$$ HPr + and HE which were used in mechanistic studies. Methylation of the amine groups was not found to prevent the reaction between the radical cation of the probe and the superoxide, but it significantly increased the lifetime of the radical cation and had a substantial effect on the profiles of the oxidation products by inhibiting the formation of dimeric products. We conclude that the N-methylated analogs of HE and $$\hbox {HPr}^{+}$$ HPr + may be used as a scaffold for the design of a new generation of probes for intra- and extracellular superoxide.

The ability to tune optical features of BODIPY materials is essential for their photo-related application. However, it is challenging to efficiently tune the crystal packing of BODIPY derivatives because of their complex nature. In this study, such control of BODIPY supramolecular assemblies was achieved by designing a BODIPY containing a halogen bond (XB) acceptor (–NO2) and donor (I, Br) to mediate halogen bonding interactions. The mono halogenated 2 and 4 was unable to form XB, whereas 3 and 5 formed isostructural mono-coordinate motif 3, 5-I (1D tubular structure) and symmetric bifurcated motif 5-II (1D zig-zag chains structure) via N-O···I,Br XB interactions. The results show that the dispersion and electrostatic component are the major source of 3, 5-I and 5-II XB formations. The XB interaction between –NO2 and X (I, Br) promote singlet-to-triplet intersystem crossing and triplet-to-singlet reverse intersystem crossing due to delocalization of oxygen electrons partially onto the Br and I. Then this interaction leads to unexpected fluorescence enhancement of 5-II. Finally, the indirect optical band gaps of the 3, 5-I and 5-II were able to be tuned in the range of 1.9–2.50 eV via XB driven crystal packings.

The ability to tune optical features of BODIPY materials is essential for their photo-related application. However, it is challenging to efficiently tune the crystal packing of BODIPY derivatives because of their complex nature. In this study, such control of BODIPY supramolecular assemblies was achieved by designing a BODIPY containing a halogen bond (XB) acceptor (–NO2) and donor (I, Br) to mediate halogen bonding interactions. The mono halogenated 2 and 4 was unable to form XB, whereas 3 and 5 formed isostructural mono-coordinate motif 3, 5-I (1D tubular structure) and symmetric bifurcated motif 5-II (1D zig-zag chains structure) via N-O···I,Br XB interactions. The results show that the dispersion and electrostatic component are the major source of 3, 5-I and 5-II XB formations. The XB interaction between –NO2 and X (I, Br) promote singlet-to-triplet intersystem crossing and triplet-to-singlet reverse intersystem crossing due to delocalization of oxygen electrons partially onto the Br and I. Then this interaction leads to unexpected fluorescence enhancement of 5-II. Finally, the indirect optical band gaps of the 3, 5-I and 5-II were able to be tuned in the range of 1.9–2.50 eV via XB driven crystal packings.

We report the first one-dimensional tubular metal-organic framework (MOF) [Ni(Cu-H6TPPA)]∙2DMA (H8TPPA = 5,10,15,20-tetrakis[p-phenylphosphonic acid] porphyrin) in the literature. The structure of this MOF, known as GTUB4, was solved using single crystal X-ray diffraction and its surface area was calculated to be 1102 m2/g, making it the phosphonate MOF with the highest reported surface area. GTUB4 also possesses a narrow indirect band gap of 1.9 eV and a direct band gap of 2.16 eV, making it a semiconducting MOF. Thermogravimetric analysis of GTUB4 suggests that it is thermally stable up to 400°C. Owing to its high surface area, low band gap, and thermal stability, GTUB4 could find applications as electrodes in supercapacitors.

The nature of halogen bonds (XBs) depending on the number and position of the XB donor (I) and acceptor (CN) groups in iodophthalonitrile derivatives such as 4-iodo-phthalonitrile (2a), 3-iodo-phthalonitrile (2b), 4,5-diiodo-phthalonitrile (2d) and 3,4-diiodo-phthalonitrile (2c) as well as in para-, ortho- and meta-iodo-substituted benzonitriles (1a–1c) was studied by X-ray analysis and ab initio calculations. Density functional theory (DFT) and the Boltzmann transport equation have been applied to calculate the semi-classical thermoelectric transport properties of the crystalline compounds of 1a–1c, 2a–2d. In 2a–2c, the molecules are consolidated into 2-D networks while in 2d the triple helix spiral staircase structure is formed due to XBs where the unusual bifurcated asymmetric XBs were observed. The Seebeck coefficients of all the studied organic semiconductors were significantly positive, suggesting that the hole-type carriers dominate the thermoelectric transport.

International audience; Four two-photon absorbing fluorophores A1–A4 are reported and their spectroscopic properties are analyzed for use, in combination with palladium–porphyrinato complexes C1 and C2, as two-photon absorbing antennas and energy donors for FRET-based antenna-core oxygen sensitive phosphorescent probes. The best antenna A3 displaying the highest biphotonic brightness Φ × σTPA = 210 GM at 800 nm was then directly grafted to the phosphorescent Pd–porphyrin cores via click chemistry to give new two-photon oxygen sensitive phosphorescent probes P1 and P2, in which energy transfer from the antenna to the core was demonstrated following two-photon excitation.

A new family of porous metal-organic frameworks (MOFs), namely alkali phosphonate MOFs, is reported. [Na2 Cu(H4 TPPA)]⋅(NH2 (CH3 )2 )2 (GTUB-1) was synthesized using the tetratopic 5,10,15,20-tetrakis[p-phenylphosphonic acid] porphyrin (H8 -TPPA) linker with planar X-shaped geometrical core. GTUB-1 is composed of rectangular void channels with BET surface area of 697 m2 g-1 . GTUB-1 exhibits exceptional thermal stability. The toxicity analysis of the (H8 -TPPA) linker indicates that it is well tolerated by an intestinal cell line, suggesting its suitability for creating phosphonate MOFs for biological applications.

International audience; Triangular shapes have inspired scientists over time and are common in nature, such as the flower petals ofoxalis triangularis, or the triangular faces of tetrahedrite crystals or on the icosahedron faces of virus capsids. Supramolecular chemistry has enabled the construction of triangular assemblies, many of which possess functional features.Among these structures, cucurbiturils have been used to build supramolecular triangles and we recently reported paramagnetic - cucurbit[8]uril (CB[8]) triangles but reasons of their formation remain unclear. Several parameters have nowbeen identified to explain their formation. At first sight, the radical nature of the guest appeared of prime importance toget the triangles and we focused on extending this concept to biradicals for obtaining supramolecular hexaradicals. Twosodium ions were systematically observed by ESI-MS in trimer structures and the presence of Na+triggered or strengthened the triangulation of CB[8]:guest 1:1 complexes in solution. X-ray crystallography and molecular modelling have allowed proposing two plausible sites of residence for the two sodium cations. We then found that a diamagnetic guestwith an H bond acceptor function is equally good at forming CB[8] triangles. Hence, a guest molecule containing a ketonefunction has been precisely triangulated thanks to CB[8] and sodium cations as determined by DOSY-NMR and DLS. Abinding constant for the triangulation of 1:1, to 3:3 complexes, is proposed. This concept has finally been extended to thetriangulation of ditopic guests toward network formation by reticulation of CB[8] triangles using dinitroxide biradicals.

Using high throughput screening-compatible assays for superoxide and hydrogen peroxide, we identified potential inhibitors of the NADPH oxidase (Nox2) isoform from a small library of bioactive compounds. By using multiple probes (hydroethidine, hydropropidine, Amplex Red, and coumarin boronate) with well defined redox chemistry that form highly diagnostic marker products upon reaction with superoxide (O2 (̇̄)), hydrogen peroxide (H2O2), and peroxynitrite (ONOO(-)), the number of false positives was greatly decreased. Selected hits for Nox2 were further screened for their ability to inhibit ONOO(-)formation in activated macrophages. A new diagnostic marker product for ONOO(-)is reported. We conclude that the newly developed high throughput screening/reactive oxygen species assays could also be used to identify potential inhibitors of ONOO(-)formed from Nox2-derived O2 (̇̄)and nitric oxide synthase-derived nitric oxide.

Nitroxide free radicals have been used to study the inner space of one of Rebek's water-soluble capsules. EPR and (1) H NMR spectroscopy, ESI-MS, and DFT calculations showed a preference for the formation of 1:2 complexes. EPR titrations allowed us to determine binding constants (Ka ) in the order of 10(7) M(-2) . EPR spectral-shape analysis provided information on the guest rotational dynamics within the capsule. The interplay between optimum hydrogen bonding upon capsule formation and steric strain for guest accommodation highlights some degree of flexibility for guest inclusion, particularly at the center of the capsule where the hydrogen bond seam can be barely distorted or slightly disturbed.

This work describes latent fluorescence particles (LFPs) based on a new environmentally sensitive carbazole compound aggregated in water and their use as sensors for probing various cavitands and the different stages of aggregating systems. Cyclodextrins (CDs), cucurbit[n]urils (CB[n], n = 6, 7, 8), and a resorcinarene capsule were used to study the dynamic nature of the LFPs. The fluorescence was dramatically enhanced by a proposed disaggregation-induced emission enhancement (DIEE) mechanism with specific features for CB[n]. Then, the aggregated states of the dipeptides Leu-Leu, Phe-Phe, and Fmoc-Leu-Leu (vesicles, crystals, fibers) were studied by fluorescence spectroscopy and confocal fluorescence microscopy thanks to the adaptive and emissive behavior of the LFPs, allowing us to study an interesting polymorphism phenomenon. The LFPs have then been used in the sensing of the aggregation of the polysaccharide alginate, for which distinct fluorescence turn-on is detected upon stepwise biopolymer assembly, and for amylose detection. The carbazole particles not only adapt to various environments but also display multicolor fluorescent signals. They can be used for the fast probing of the aggregation propensity of newly prepared molecules or biologically relevant compounds or to accelerate the discovery of new macrocycles or of self-assembling peptides in water.

Novel nickel (II) phthalocyanines carrying four branched thia- and oxy-oligo(ethyleneoxy) groups on peripheral and non-peripheral positions have been synthesized from the corresponding phthalonitrile derivatives. The new compounds have been characterized by elemental analysis, mass spectrometry, infrared, nuclear magnetic resonance, and ultraviolet–visible spectroscopy. The spectroscopic properties and aggregation behaviors of these phthalocyanine complexes have been studied in different solvents and concentrations. The mesogenic properties of these new materials have been determined by differential scanning calorimetry, optical polarized microscopy and X-ray diffraction investigations. The effects of the substituents’ position ( α or β ) and the nature of the linker heteroatom (O or S) on the mesogenic properties of the synthesized nickel (II) phthalocyanines have also been explained.

The octupolar cube, a T-d symmetry cube presenting alternating charges at its corners, is the generic point charge template of any octupolar molecule. So far, transposition into real molecular structures has yet to be achieved. We report here a first step toward the elaboration of fully cubic octupolar architectures. A series of octupolar bis(2,3,16,17-tetra(hexylthio)phthalocyaninato)lanthanide double-decker complexes [Pc(2)Ln], Ln = Nd (1), Eu (2), Dy (3), Y (4), and Lu (5), are described, whose original three-dimensional structures display the required alternation of ABAB type for one face of the cube and the delocalization between the two rings approximating to the electronic interaction along the edges of the cube. Synthesis, X-ray crystal structure, and study of the optical properties and of the first molecular hyperpolarizability beta are reported. The size of the lanthanide (III) central ion modulates the ring-to-ring distance and the degree of coupling between the two phthalocyanine rings. As a consequence, the optical properties of these octupolar chromophores and in particular the strong near-infrared absorption due to the intervalence transition between the two rings also depend on the central lanthanide (III) ion. The first oxidized and reduced states of the complexes, while keeping a similar octupolar structure, display considerably changed optical properties compared to the neutral states. Second-order nonlinear properties were determined by nonpolarized harmonic light scattering in solution at 1907 nm. Exceptionally large dynamic molecular first hyperpolarizabilities root (1907), among the highest ever reported, were found that showed a strong dependence on the number of 4f electrons.

We describe a photochemical method to introduce a single alcohol function directly on cucurbit[n]urils (n = 5, 6, 7, 8) with conversions of the order 95-100% using hydrogen peroxide and UV light. The reaction was easily scaled up to 1 g for CB[6] and CB[7]. Spin trapping of cucurbituril radicals combined with MS experiments allowed us to get insights about the reaction mechanism and characterize CB[5], CB[6], CB[7], and CB[8] monofunctional compounds. Experiments involving 18O isotopically labeled water indicated that the mechanism was complex and showed signs of both radical and ionic intermediates. DFT calculations allowed estimating the Bond Dissociation Energies (BDEs) of each hydrogen atom type in the CB series, providing an explanation of the higher reactivity of the "equatorial" C-H position of CB[n] compounds. These results also showed that, for CB[8], direct functionalization on the cucurbituril skeleton is more difficult because one of the methylene hydrogen atoms (Hb) has its BDE lowering within the series and coming close to that of Hc, thus opening the way to other types of free radicals generated on the CB[8] skeleton leading to several side products. Yet CB[5]-(OH)1 and CB[8]-(OH)1, the first CB[8] derivative, were obtained in excellent yields thanks to the soft method presented here.

International audience; In this work, the synthesis and the nonlinear absorption and population dynamics investigation of a series of zinc phthalocyanines (ZnPcs) dissolved in chloroform are reported. In order to determine the relevant spectroscopic parameters, such as absorption cross-sections of singlet and triplet excited states, fluorescence relaxation times, intersystem crossing, radiative decay and internal conversion, different optical and spectroscopic techniques were used. By single pulse and pulse train Z-scan techniques, respectively, singlet and triplet excited states‘ absorption cross-section were determined at 532 nm. Furthermore, the intersystem crossing time was obtained by using both techniques combined with the fluorescence lifetime determined by time-resolved fluorescence. The radiative and internal conversion rates were determined from the fluorescence quantum yield of the samples. Such spectroscopy parameters are fundamental for selecting photosensitizers used in photodynamic therapy, as well as for many other applications.

Ni(II) and Zn(II) phthalocyanines carrying four or eight branched oligo(ethyleneoxy)-thia groups on peripheral positions have been synthesized from new phthalonitrile derivatives. The new compounds have been characterized by elemental analysis, IR, NMR, mass spectra and electronic spectroscopy. The aggregation behaviors of the phthalocyanine complexes were studied in different solvents and concentrations. General trends are described for photodegradation, singlet oxygen and fluorescence quantum yields, and fluorescence lifetimes of these compounds in dimethylsulfoxide (DMSO). The effects of the substitution on the photophysical and photochemical parameters of the nickel(II) (3a and 4a) and zinc(II) phthalocyanines (4b) are also reported. The octasubstituted zinc(II) complex (3b) is not stable for these measurements. Preliminary investigation of the photophysical and photochemical properties of phthalocyanine complexes are very useful for further PDT applications. The mesogenic properties of these new materials were studied by differential scanning calorimetry (DSC), optical polarized microscopy and X-ray investigations.

Two novel, nickel phthalocyanines bearing peripherally alpha(α)-substituents, namely octa(1,3-bis(dodecyloxy)propan-2-ol) and octa(1,3-bis[2-(2-ethoxyethoxy)ethoxy]propan-2-ol) were synthesized by cyclotetramerisation of the corresponding nitriles. At room temperature, the peripherally α-substituted Ni(II) phthalocyanine complexes exhibited a relatively viscous liquid state; their spectroscopic properties and aggregation behaviour were investigated in different solvents and at different concentrations in chloroform. The two compounds showed Q-bands in the near-IR region of the electronic spectrum and did not aggregate in all solvents and under a wide range of concentrations in chloroform.

The (15-oxo-3,7,11-triazadispiro[5.1.5.3]hexadec-7-yl)oxidanyl, a bis-spiropiperidinium nitroxide derived from TEMPONE, can be included in cucurbit[7]uril to form a strong (Ka ∼ 2 × 105 M−1) CB[7]@bPTO complex. EPR and MS spectra, DFT calculations, and unparalleled increased resistance (a factor of ∼103) toward ascorbic acid reduction show evidence of deep inclusion of bPTO inside CB[7]. The unusual shape of the CB[7]@bPTO EPR spectrum can be explained by an anisotropic Brownian rotational diffusion, the global tumbling of the complex being slower than rotation of bPTO around its “long molecular axis” inside CB[7]. The CB[7] (stator) with the encapsulated bPTO (rotator) behaves as a supramolecular paramagnetic rotor with increased rotational speed of the rotator that has great potential for advanced nanoscale machines requiring wheels such as cucurbiturils with virtually no friction between the wheel and the axle for optimum wheel rotation (i.e. nanopulleys and nanocars)., Nanoscale, 7 (28), ISSN:2040-3364, ISSN:2040-3372

A series of zinc phthalocyanines (ZnPcs) tetra-substituted with 1,3-di[2-(2-ethoxyethoxy)ethoxy]-2-propanol (1a) or 1,3-di[2-(2-ethoxyethoxy)ethoxy]-2-propanethiol (1b) at peripheral (β) (6a–b) and non-peripheral (α) (7a–b) positions have been synthesized and characterized. The spectroscopic, photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation and photodegradation) properties of these newly synthesized phthalocyanines have been investigated in DMSO. The effects of the position of the substituents on the phthalocyanine skeleton and the nature of the linker heteroatom on their spectroscopic, photophysical and photochemical properties have been determined. The quenching behavior of the zinc phthalocyanines by 1,4-benzoquinone has been studied in DMSO. All of the zinc(II) Pc complexes (6a–b and 7a–b) showed similar electronic absorption spectra in various solvents (chloroform, dichloromethane, DMF, DMSO, THF and toluene). However, complex 7a gave an extra red-shifted band at 742 nm in chloroform and dichloromethane. DFT and TD-DFT computations were performed on the model structures (8a–d, pp-8a–d and 9a–d) to find out the cause of the extra red-shifted Q band (J-type aggregation or protonation of the Pc ring). The computational results showed that monoprotonation of a meso nitrogen atom leads to the formation of this extra band. Photophysical and photochemical measurements indicated that these newly synthesized ZnPc derivatives are promising candidates for use as photosensitizers in the application of PDT.

During our follow-up work on the conjugation of monohydroxylated cucurbiturils, we found that the reported yields of monohydroxylation of CB[n] (n = 5−8), 90−95%, were incorrect. This was due to the misleading composition of the crude product, with an approximate 0.3/0.3/0.3 ratio of CB[n], CB[n]−(OH)1, and CB[n]−(OH)2, giving NMR signal integrals and peak positions that match the expected values for pure CB[n]−(OH)1. After purification of the product via silica column chromatography using water/acetic acid/formic acid as eluent, the corrected yields are 5−37% for CB[n]− (OH)1, with n = 5−8. These results were confirmed by repeated experiments starting with 100 mg, and using up to 3 g, of CB[n]. The Supporting Information has been revised to include MS spectra of pure CB[n]−(OH)1 and details of the column chromatography purification procedure for all CB[n]−(OH)1. Page 10238. The title should be revised to Comprehensive Synthesis of Monohydroxy−Cucurbit[n]urils (n = 5, 6, 7, 8). Page 10238. In the Abstract, the 95−100% conversion reported for CB[n]−(OH)1 should be corrected to 20−40%, depending on the CB[n] considered. Scale-up experiments were performed using up to 3 g of CB[n] with quartz reactors of 50 or 300 mL. Page 10239. In the Synthesis section, the conversions given in the text and in Table 1 are incorrect due to the misleading H NMR spectra, and should actually be 20−40%. The values in Table 1 are thus apparent conversions determined by H NMR. Isolated yields have been determined and are given in the revised Supporting Information (5−37% for the CB[n]− (OH)1 series). Page 10242. In Table 3, likewise, the conversion of CB[8] toward the formation of CB[8]−(OH)1 is an apparent conversion determined by H NMR, where CB[8] is transformed to CB[8]−(OH)1 and CB[8]−(OH)2. Thus, the title of the table should be revised to “Apparent Conversion of CB[8] toward the Formation of CB[8]−(OH)1”. ■ ASSOCIATED CONTENT *S Supporting Information The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/jacs.6b00188. Procedure for the preparation of CB[n]−(OH), C NMR spectra, details of high resolution MS analyses, decay products of CB[8], details for the calculations of BDEs, and structures of each CB[n]· radical (revised) (PDF)

The concept of octupolar molecules has considerably enlarged the engineering of second-order nonlinear optical materials by giving access to 2D and 3D architectures. However, if the archetype of octupolar symmetry is a cube with alternating donor and acceptor groups at the corners, no translation of this ideal structure into a real molecule has been realized to date. This may be achieved by designing a bis(phthalocyaninato)lutetium(III) double-decker complex with a crosswise ABAB phthalocyanine bearing alternating electron-donor and electron-acceptor groups. In this communication, we present the first step toward this goal with the synthesis, crystal structure determination, and measurement of the molecular first-order hyperpolarizability beta by harmonic light diffusion, of an original lutetium(III) sandwich complex displaying the required ABAB-type alternation for one face of the cube. This structure is characterized by an intense absorption in the near-IR due to an intervalence transition and exhibits the highest quadratic hyperpolarizability ever reported for an octupolar molecule, root )(HLS)(1907) = 5750 X 10(-30) esu.

International audience; The use of visible absorbing and fluorescent tags for sensing and structural analysis of carbohydrates is a promising route in a variety of medical, diagnostic, and therapeutic contexts. Here we report an easy method for covalent attachment of nonfluorescent push-pull chromophores based on the 4-cyano-5-dicyanomethylene-2-oxo-3-pyrroline ring to carbohydrate moieties. The impact of sugar grafting on the optical properties of the push-pull chromophore in the gas phase and in solution was investigated by absorption and action spectroscopy and theoretical methods. The labeled sugars efficiently absorb photons in the visible range, as demonstrated by their intense photodissociation in a quadrupole ion trap. A strong blue shift (-70 nm) of the gas-phase photodissociation intensity maximum is observed upon sugar grafting, whereas no such effect is visible on the solution absorption spectra. Molecular dynamics simulations of labeled maltose in the gas phase describe strong interactions between the sulfonated chromophore and the carbohydrate, which lead to cyclic conformations. These are not observed in the simulations with explicit solvation. Time-dependent density functional theory (TD-DFT) calculations on model molecules permit us to attribute the observed shift to the formation of such cyclic conformations and to the displacement of the negative charge relative to the aromatic moiety of the chromophore.

International audience; Selected Reaction Monitoring (SRM) carried out on triple-quadrupole mass spectrometers coupled to liquid chromatography has been a reference method to develop quantitative analysis of small molecules in biological or environmental matrices for years and is currently emerging as a promising tool in clinical proteomic. However, sensitive assays in complex matrices are often hampered by the presence of co-eluted compounds that share redundant transitions with the target species. On-the-fly better selection of the precursor ion by high-field asymmetric waveform ion mobility spectrometry (FAIMS) or increased quadrupole resolution is one way to escape from interferences. In the present work we document the potential interest of substituting classical gas-collision activation mode by laser-induced dissociation in the visible wavelength range to improve the specificity of the fragmentation step. Optimization of the laser beam pathway across the different quadrupoles to ensure high photo-dissociation yield in Q2 without detectable fragmentation in Q1 was assessed with sucrose tagged with a push-pull chromophore. Next, the proof of concept that photo-SRM ensures more specific detection than does conventional collision-induced dissociation (CID)-based SRM was carried out with oxytocin peptide. Oxytocin was derivatized by the thiol-reactive QSY® 7 C(5)-maleimide quencher on cysteine residues to shift its absorption property into the visible range. Photo-SRM chromatograms of tagged oxytocin spiked in whole human plasma digest showed better detection specificity and sensitivity than CID, that resulted in extended calibration curve linearity. We anticipate that photo-SRM might significantly improve the limit of quantification of classical SRM-based assays targeting cysteine-containing peptides.

Among possible asymmetrically substituted phthalocyanines, ABAB derivatives remain rare. Their selective synthesis is based on the use of trichloroisoindolenines, so far remaining tedious to obtain. An optimized synthesis of 1,3,3-trichloroisoindolenine 1 and 1,3,3,6,7-pentachloroisoindolenine 2 is reported. An original crystallization method based on crystal growth by sublimation was eminently suitable regarding the air-sensitivity of these derivatives and allowed their thorough crystallographic characterization.