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The high risk of CO poisoning justifies the need for indoor air quality control and warning systems based on the detection of low concentrations (ppm‐ppb) of CO. Cobalt corrole complexes selectively bind CO vs. O2, CO2, N2, opening new fields of applications. By combining the CO chemisorption properties of cobalt corroles with the known sorption capacity of MOFs, we hope to obtain high performance sensing materials for CO detection. In addition, the exposed metal sites of MOFs lead to CO2 physisorption, allowing the co‐detection of CO and CO2. In this work, PCN‐222, a stable Zr‐based MOF made from Ni(TCPP) with natural vacancies, has been used as a porous matrix for the grafting of electron‐poor metallocorroles. The materials were characterized by powder XRD, SEM and optical microscopy, BET analyses and gas adsorption measurements at 298 K. No degradation of the crystalline structure of PCN‐222 was observed. At 1 atm, the adsorbed CO(g) volumes measured for the best materials were 12.15 cm3 g−1 and 14.01 cm3 g−1 for CoCorr2@PCN‐222 and CoCorr3@PCN‐222 respectively, and both materials exhibited high CO chemisorption and selectivity against O2, N2, and CO2 at low pressure due to the highest energy of the chemisorption process vs physisorption. [ABSTRACT FROM AUTHOR]

Molecular layer deposition (MLD) is an incredibly powerful and flexible tool for designing completely new materials with novel and unique properties. The low temperature layer‐by‐layer approach and the use of highly reactive reactants allows one to combine vastly different organic and inorganic species and construct nanostructures with subnanometer precision. If not limited by the volatility of the reactants involved, the possibilities will be endless. This is most notable for the organic building blocks where an overall low volatility severely limits the toolbox of large molecules with interesting optical and electrical properties such as red‐ox activity and optical conversion. In this work, different strategies for molecular design of large molecules are investigated that allow vaporization while still having the necessary reactivity for MLD growth. Using these strategies, film growth with perylene and porphyrin derivatives, both molecules well known for their functional and optical properties are successfully achieved. With this knowledge, there is an opening to include much larger and more complex organic molecules into the world of vapor phase chemistry. [ABSTRACT FROM AUTHOR]

Four bis‐ammonia ligated cobalt corroles and four mono‐DMSO ligated cobalt corroles with different meso‐aryl substituents on the macrocycle (A2B‐ and A3‐corroles) were synthesized and investigated as to their electrochemical and spectroscopic properties under different solution conditions. The complexation energies of the investigated cobalt corroles were theoretically calculated to illustrate the propensity of the cobalt center for penta‐coordination or hexa‐coordination with various axial ligands (DMSO, CO, py and NH3). The structure of one hexacoordinate bis‐NH3 cobalt corrole complex was also determined by X‐ray diffraction. Four bis‐ammonia ligated cobalt corroles and four mono‐DMSO ligated cobalt corroles with different meso‐aryl substituents on the macrocycle (A2B‐ and A3‐corroles) were synthesized and investigated as to their electrochemical and spectroscopic properties under different solution conditions. [ABSTRACT FROM AUTHOR]

Abstract: A series consisting of a dyad, a triad and a tetrad containing either two, three and four BODIPY units, respectively, has been synthesized and fully characterized and compared to two mono‐BODIPY analogs (used as references). The one‐ and two‐photon photophysical properties have been measured and the X‐ray structures of four of the BODIPY derivatives have been determined. In the 700–900 nm range, the two‐photon absorption (TPA) cross sections range from 30 GM to 160 GM for these compounds. [ABSTRACT FROM AUTHOR]

A series of open-chain pentapyrroles and sapphyrins with highly electron-withdrawing substituents (i.e., CN, CF3, or CO2Me) on the meso-phenyl rings was synthesized and characterized as to the spectral properties, protonation reactions, and electrochemistry in non-aqueous media. The investigated compounds are represented as (Ar)4PPyH3 and (Ar)4SapH3 where PPy and Sap correspond to the tri-anion of the open-chain pentapyrrole and sapphyrin, respectively, and Ar= p-CNPh, p-CF3Ph, or p-CO2MePh. UV/Vis and 1H NMR spectroscopy as well as mass spectrometry data are given for the confirmation of the structures for the newly synthesized compounds. An X-ray structure for one of the pentapyrroles, that is, ( p-CF3Ph)4PPyH3 ( 2), is also presented. The protonation processes were examined by UV/Vis absorption spectroscopy during the titration of the compounds with trifluoroacetic acid (TFA) in CH2Cl2. Equilibrium constants for the protonation reactions were calculated by using both the Hill equation and the mole ratio method. The protonation-initiated conversion of pentapyrroles to sapphyrins upon oxidation was also investigated. Cyclic voltammetry was used to measure the redox potentials in CH2Cl2, PhCN, and/or pyridine (Py). Electrochemical properties, protonation constants, and chemical reactions of the six compounds in the two series were then analyzed as a function of the solvent properties and the type of the electron-withdrawing groups on the meso-phenyl rings. [ABSTRACT FROM AUTHOR]

The protonation and electrochemical properties of positively charged and negatively charged porphyrins are reported in up to five different nonaqueous solvents. The positively charged porphyrins are represented by mono- and di-pyridyl derivatives having the formula Py x(PhMe)4- xPM, where P=the dianion of the porphyrin macrocycle, PhMe is a meso-tolyl group, Py a meso-pyridyl group, x=1 or 2, and M=H2, NiII, CuII, ZnII, or CoII. The negatively charged porphyrins are comprised of meso-tetrasulfonato derivatives having the formula [(R)4(TPPS)H2]4−(X+)4, where [(TPPS)H2]4− represents the porphyrin with four SO3− groups on the meso-phenyl substituents of the macrocycle, R=H or PEG (PEG=C7H15O4) and X+=H+ or Na+. Each pyridylporphyrin was shown to undergo an initial protonation of the meso-pyridyl group(s) upon addition of acid to the porphyrin solutions and, in the case of the free-base derivatives, this was followed in a second step by a simultaneous protonation of the two core nitrogen atoms on the macrocycle. Two central nitrogen atoms of the sulfonatophenyl porphyrins are also protonated in a single-step process, and the constants for each protonation reaction of Py x(PhMe)4- xPM and [(R)4(TPPS)H2]4−(X+)4 were determined through spectral titration with trifluoroacetic acid in DMF, DMSO, CH2Cl2, or PhCN, after which the data were related to solvent properties, the measured redox potentials, and the mechanisms for electroreduction under the same solution conditions. [ABSTRACT FROM AUTHOR]

An original corrole-containing polyad for S1 energy transfer, in which one zinc(II)-porphyrin donor is linked to two free-base corrole acceptors by a truxene linker, is reported. This polyad exhibits a rapid zinc(II)-porphyrin*→free-base corrole transfer (4.83×1010 s−1; 298 K), even faster than the tautomerization in the excited state processes taking advantage of the good electronic communication provided by the truxene bridge. Importantly, the energy transfer process shows approximately 3-fold selectivity for one corrole N−H tautomer over the other even at low temperature (77 K). This selectivity is due to the difference in the J-integral being effective in both the Förster and Dexter mechanisms. The data are rationalized by DFT computations. [ABSTRACT FROM AUTHOR]

A porphyrin--diketopyrrolopyrrole-containing polymer (poly(porphyrin--diketopyrrolopyrrole) (PPDPP)) shows impressive molar absorption coefficients from λ=300 to 1000 nm. The photophysical and structural properties ofPPDPP have been studied. With PPDPP as the electron donor and [6,6]-phenyl C71 butyric acid methyl ester (PC71BM) as the electron acceptor, the bulk heterojunction polymer solar cell showed overall power conversion efficiencies of 4.18 and 6.44% for as-cast and two-step annealing processed PPDPP:PC71BM (1:2) active layers, respectively. These results are quite impressive for porphyrin-containing polymers, especially when directly included in the π-conjugated backbone, and offer interesting perspectives for the design of new materials based on this chromophore. [ABSTRACT FROM AUTHOR]

The synthesis of dyad and triad aza-BODIPY-porphyrin systems in two steps starting from an aryl-substituted aza-BODIPY chromophore is described. The properties of the resulting aza-BODIPY-porphyrin conjugates have been extensively investigated by means of electrochemistry, spectroelectrochemistry, and absorption/emission spectroscopy. Fluorescence measurements have revealed a dramatic loss of luminescence intensity, mainly due to competitive energy transfer and photoinduced electron transfer involving charge separation followed by recombination. [ABSTRACT FROM AUTHOR]

A detailed study of reduction potentials, electroreduction mechanisms, and acid-base chemistry was carried out on two series of free-base porphyrins in nonaqueous media. The first series is represented by four β-pyrrole-substituted tetraphenylporphyrin (TPP) derivatives, two of which are planar and two of which are nonplanar in their nonprotonated form. The second comprises porphyrins with 0-4 meso-phenyl groups on the macrocycle. Equilibrium constants for the conversion of each neutral porphyrin to its diprotic [H4P]2+ form were determined and the electrochemistry was then elucidated as a function of: 1) type of nonaqueous solvent, 2) anion of supporting electrolyte, 3) porphyrin ring substituents, and 4) concentration of acid added to solution. Spectroelectrochemistry was used to characterize absorption spectra of each electroreduced species and, when combined with results of the above studies, significantly improves our ability to tune redox reactivity of these types of compounds. [ABSTRACT FROM AUTHOR]

Twelve structurally related pyridyl and meso- N-methylpyridylporphyrin derivatives are investigated electrochemically in different nonaqueous media. The UV/Vis spectrum of each newly investigated porphyrin was measured before and after electroreduction and, based on this data, the site of electron transfer is proposed. An interaction occurs between the meso-pyridyl or meso- N-alkyl-4-pyridyl substituents and the porphyrin π-ring system, the magnitude of which depends upon the number of linked pyridyl or N-alkyl-4-pyridyl groups in the compound, the solvent, the supporting electrolyte, and/or other anions added to the solution. [ABSTRACT FROM AUTHOR]

Herein the synthesis, spectroscopic characterization, two-photon absorption and electrochemical properties of 3,6-disubstituted carbazole tweezers is reported. A dimer resulting from a Glaser homocoupling was isolated during a Sonogashira coupling reaction between a diethynyl-carbazole spacer and a 5-bromo-triarylporphyrin and the properties of this original compound were compared with the 3,6-disubstituted carbazole bisporphyrin tweezers. The dyads reported herein present a two-photon absorption maximum at 920 nm with two-photon absorption cross-section in the 1200 GM range. Despite a strong linear absorption in the Soret region and moderate fluorescence quantum yield, they both lead to a high brightness reaching 30 000 M−1 cm−1. [ABSTRACT FROM AUTHOR]

A series of four multimodal ligands incorporating one porphyrin moiety and one or more dota-like macrocycles all-in-one in the same molecular architecture have been synthesized and full characterized. The corresponding gadolinium(III) complexes were also synthesized and heterometallic complexes incorporating both gadolinium(III) and copper(II) ions were prepared as potential MRI/PET multimodal contrast agents. One ligand ( L4) includes an amine moiety that can be activated for easy conversion into an isothiocyanate group for further anchoring to a biological vector. Preliminary relaxivity, cytotoxicity, and MRI studies showed that the complexes developed in this work are very promising medical-imaging agents for the enhancement of contrast in bimodal MRI techniques. [ABSTRACT FROM AUTHOR]

An original corrole‐containing polyad for S1 energy transfer, in which one zinc(II)porphyrin donor is linked to two free base corrole acceptors by a truxene linker, is reported. This polyad exhibits a rapid zinc(II) porphyrin*→free‐base corrole transfer, even faster than the tautomerization in the excited state processes taking advantage of the good electronic communication provided by the truxene bridge. For more details see the Full Paper by C. P. Gros, P. D. Harvey et al. on page 5010 ff. [ABSTRACT FROM AUTHOR]

Two ‐ photon absorption and electrochemical properties of carbazole ‐ linked porphyrin tweezers including a bisporphyrin dimer resulting from a Glaser homocoupling have been prepared and fully characterized by C. P. Gros, F. Bolze, K. M. Kadish, and co ‐ workers. The dyads reported present a two ‐ photon absorption maximum at 920 nm with two ‐ photon absorption cross ‐ section in the 1200 GM range. The comprehensive report can be found in the Full Paper on page 12018 ff. [ABSTRACT FROM AUTHOR]