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Porphyrins are conjugated, stable chromophores with a central core that binds a variety of metal ions and an easily functionalized peripheral framework. By combining the catalytic, electronic or cytotoxic properties of selected transition metal complexes with the binding and electronic properties of porphyrins, enhanced characteristics of the ensemble are generated. This review article focuses on porphyrins bearing one or more peripheral transition metal complexes and discusses their potential applications in catalysis or biomedicine. Modulation of the electronic properties and intramolecular communication through coordination bond linkages in bis‐porphyrin scaffolds is also presented. See the future of porphyrin‐metal conjugates: Appending transition metal complexes to the periphery of porphyrins, renowned for their photo‐ and electro‐activity, opens new avenues for applications in electron‐ or photon‐triggered catalytic reactions, optoelectronic properties of self‐assembled materials, and therapeutic or diagnostic tools in biomedicine. [ABSTRACT FROM AUTHOR]

A new class of multifunctional silica nanoparticles carrying boron clusters (10-vertex closo-decaborate) and incorporating luminescent centers (fluorescein) has been developed as potential probes/carriers for potential application in boron neutron capture therapy (BNCT). These silica nanoparticles were charged in situ with silylated-fluorescein fluorophores via the Stöber method and their surface was further functionalized with decaborate-triethoxysilane precursors. The resulting decaborate dye-doped silica nanoparticles were characterized by TEM, solid state NMR, DLS, nitrogen sorption, elemental analysis, and fluorescence spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: The bis(silylated) alkenes Z-(PhSCH2)Me2SiC(H)2(CH2SPh) (2) and Z-(PhSCH2)Me2SiC(H))SiMe2(CH2SPh) (3) have been prepared by Pd-catalyzed double silylation of ethynylferrocene and 4-ethynyl-1,1′-biphenyl in the presence of 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane (1). A reinvestigation on the interaction of 1 with [PdCl2(PhCN)2] in technical-grade CH2Cl2 as solvent revealed competition between reduction to elemental palladium (due to oxidative addition of the Si–Si bond across Pd(II) and subsequent reductive elimination) and formation of an unusual eight-membered chelate complex cis-[PdCl2{(PhSCH2SiMe2)2O}] (4), which is fluxional in solution. Based on GC–MS analyses revealing both formation of chlorosilane ClSiMe2CH2SPh and the disiloxane (PhSCH2SiMe2)2O, residual water contained in CH2Cl2 is supposed to be the source for the oxygen atom of the siloxane function. The mechanism of the formation of 4 is discussed. The molecular structures of 1 and 4 were determined by single-crystal X-ray diffraction analyses. The energies of several conformational isomers of 4 were computed by means of DFT calculations, the coexistence of a species featuring a weak dative Pd–O interaction due to a hemi-labile coordination of ligand 1 was evidenced. [Copyright &y& Elsevier]

Abstract: A series of alkynyl cobalt complexes [Co2(μ-η2-HCC–PCP)(CO)6−n L n ] [n = 0 (2); n = 2, L2 = dppa (3), dppm (4), dcpm (6), 2 P(OPh)3 (7)] and [Co2(CO)4L2]2(μ-η2:μ-η2-HCC–PCP–CCH)] (L2 = dppm (8), dcpm (9); (PCP = [2.2]paracyclophane) has been prepared and characterized. The molecular structures of 3 and 4, as well as that of [Co2(CO)4(μ-CO)2(μ2-dcpm)] (5), have been determined by X-ray diffraction. Electrochemical studies (Cyclic Voltammetry, Rotating Disk Electrode) and luminescence spectroscopy have been used to evaluate the extent of the electronic communication through the PCP motif using the “Co2C2” centres as a probe. No electronic coupling between the Co2(CO) n centres via the bridging PCP-ligand was evidenced neither by electrochemistry nor by luminescence measurements in diyne complexes. [Copyright &y& Elsevier]

The self-assembly of functional polythiophenes was studied by a bottom-up approach "from molecule to polymer". The synthesis and the X-ray structure of 2,5-dibromo-3-styryl and 3-2′,3′,4′,5′,6′-pentafluorostyryl-thiophenes revealed a supramolecular arrangement controlled by π-π interactions between the aromatic rings. A [2 + 2] photocyclization reaction in the solid state of (E)-1-2′,5′-dibromo-3′-thienyl-2-pentafluorophenylethene triggers the formation of a rare cycloadduct comprising thiophene rings. The X-ray analysis confirmed its rctt stereochemistry. The synthesis of P3HT-b-P3ST and P3HT-b-P3STF block oligomers was achieved by a GRIM method in good yields. An indirect proof of well-defined nanostructured organization was provided by the partial photocyclization of pendant styryl moieties under UV irradiation. [ABSTRACT FROM AUTHOR]

The homodinuclear [CIM(μ-dppm)2MCI] complexes 1 (M = Pd) and 2 (M = Pt) react with RNC ligands (R = Ph, xylyl, p-tolyl, p-C6H4iPr) to provide the A-frame [CIPd(μ-dppm)2(μ-C=N-R)PdCI] (R = Ph (5a), xylyl (5b)), [CIPt(μ-dppm)2(μ-C=N-R)PtCI] (R = p-tolyl (4a); p-C6H4iPr (4b)), and the d9-d9 M2-bonded [CIPt(μ-dppm)2Pt(CN-R)]Cl (R = xylyl (3a); p-C6H4iPr (3b)) complexes. The heterodinuclear [XPd(μ-dppm)2PtX] complexes 6a (X = Cl) and 6b (X = I) react with RNC (R = o-anisyl) to form the A-frame [XPd(μ-dppm)2(μ-C=N-R)PtX] (X = Cl (9); I (10a)) and M2-bonded [CIPt(μ-dppm)2Pt(CN-R)]Cl (10b) complexes. The dangling ligand-containing complex [CIPd(u- dppm)2Pt(η1-dppm=O)](BF4) (7) reacts with xylyl-NC stoichiometrically to produce the dicationic salt [(xylyl-NC)Pd(μ-dppm)2Pt(η1-dppm=O)](BF4)2 (8). Parameters ruling the coordination site terminal versus bridging are discussed. The precursor 10a reacts with RNC (R = o-anisyl, tBu) to form the heterobimetallic bis(isonitrile) [lPd(μ-dppm)2(μ-C=N-o-anisyl)Pt(CN-R)]l complexes 11b and 12, respectively, demonstrating the site selectivity of the second CNR ligand coordination, Pd versus Pt. The X-ray structures of 11b and 12 were obtained. Complex 12 is the first example of an A-frame system of the Ni-triad bearing two different isocyanide ligands. Several d9-d9 terminal and d8-d8 A-frame homo- and heterodinuclear complexes in 2-MeTHF at 77 K were studied by UV-vis and luminescence spectroscopy. Assignments for the lowest energy absorption and emission bands are made on the basis of density functional theory and time-dependent density functional theory computations. [ABSTRACT FROM AUTHOR]

The new conjugated organometallic polymer (spacerC≡CPt(PBu3)2C≡C)n (3; spacer = para-bis(diphenyl(tetramethyl)quinone diimine) and the cyclic mononuclear model complex, spacer′C≡CPt(PEt3)2C≡C·CuCl (4; spacer′ = ortho-diphenyl-2,3,5,6-tetramethyl-1,4-benzoquinone diimine) were synthesized from the 1:1 condensation of the corresponding diethynyl ligands (2-para and 2-ortho (para- and ortho-diethynyl-diphenyl-2,3,5,6-tetramethylquinone diimine), respectively), with the trans-Pt(PBu3)2Cl2 for polymer 3 and cis-Pt(PEt3)2Cl2 for 4. The materials were characterized by GPC, DSC, ATG, and electrochemistry for polymer 3, and by X-ray diffraction for 4. Polymer 3 exhibits a Mn of 18500, Mw of 25000 with a PD of 1.37. The trans-geometry about Pt in polymer 3 was confirmed by31 P NMR and IR/Raman spectroscopy. The cyclic voltammogram study on the model complex trans-Pt(PBu3)2(C≡CPh)2, spacer 1-para (Me3SiC≡CRC≡CSiMe3; R = para-diphenyl-2,3,5,6-tetramethyl-1,4-benzoquinone diimine) and polymer 3 demonstrated that polymer 3 in the presence of trifluoroacetic acid (TFA) exhibits a quasi reversible 2-electron reduction process centered at 0.48 V versus SCE corresponding to the reduction of the protonated quinone diimine unit into the corresponding diamine. The UV-vis spectra of the spacer 2-para (440 nm) and polymer 3 (502 nm) are characterized by red-shifted charge transfer (CT) absorptions (C6H4C≡C → quinone diimine for 2-para; and (C6H4C≡C)2Pt → quinone diimine for polymer 3). These assignments are corroborated by density-functional theory (DFT) and time-dependent density-functional theory (TDDFT) computations. Polymer 3 is not luminescent in the solid state or in solution at 77 K and 298 K. [ABSTRACT FROM AUTHOR]

The homodinuclear d9-d9 CIM(μ-dppm)2MCl2 complexes, 1 (M = Pt) and 2 (M = Pd) react with the conjugated and luminescent PCP-NC ligand (3, PCP = [2.2]paracyclophane) to provide the corresponding d9-d9 terminal [ClPt(μ-dppm)2Pt(CN-PCP)]Cl (4) and d8-d8 A-frame [CIPd(μ-dppm)2(μ-C=N-PCP)PdCl] (5) isocyanide complexes, respectively. These two bimetallic complexes were characterized by IR, 1H, and 31P{1H} NMR and by chemical analysis. IR data (υ(CN) bridging vs terminal) reveal a terminal isocyanide bonding mode for 4 (2147 cm-1) and an A-frame structure for 5 (1616 cm-1). The optical and emission properties of the free isocyanide 3 as well as those of the homodinuclear complexes 4 and 5 were studied by UV-visible and luminescence spectroscopy and by photophysical measurements. The unexpected presence of simultaneous intraligand μμ* fluorescence and phosphorescence attributable to the organic PCP-NC ligand, as well as luminescence from the inorganic M2- bonded Pt2(μ-dppm)2 center arising from a lower energy excited LMCT state (ligand-to-metal-charge-transfer) for 4 at 77 K, indicates a weak conjugation between the two chromophores and an absence of efficient singlet and triplet energy transfers. For 5, only the fluorescence and phosphorescence bands of the PCP-NC ligand are observed [since the A-frame XPd(μ-dppm)2(μ-L)PdX (L = isocyanide, X halide) is not luminescent], stressing that the N≡C bridge exhibits modest electronic communication properties. [ABSTRACT FROM AUTHOR]

ClPd(μ-dppm)PtCl ( 1) reacts with (CNCH-2-OCH-) to form a sparingly soluble and thermally stable orange polymeric material 4. 1 reacts with 1 or 2 equivalents of CNCH-2-OCH to form the soluble A-frame d-d model complexes 2 [ClPd(μ-dppm)(μ-CNR)PtCl], and 3 [ClPd(μ-dppm)(μ-CNR)Pt(CNR)](Cl) (R = CH-2-OCH), respectively. IR (ν(NC) bridging versus terminal) and NMR data reveal an A-frame structure where the terminal CNR ligands are bonded to Pt. 4 which is amorphous (XRD) appears stable up to 290 °C (TGA), but exhibits an exothermic process between 215 and 255 °C upon the first scan in DSC, but disappears upon the second. Two compounds, model 2 (λ = 674 nm; τ = 0.38 ± 0.01 μs; Φ = 0.0079 (±10%)) and polymer 4 (λ = 660 nm; τ = 0.18 ± 0.01 μs; Φ = 0.0056 (±10%)) are luminescent at 77 K in the solid state and in fluid solution (PrCN). Graphical abstract: The First A-Frame-Containing Organometallic Polymer: Taking Advantage of the Site Selectivity in PdPt-Mixed Metal Bimetallics Sébastien Clément, Shawkat Mohammed Aly, Karl Gagnon, Alaa S. Abd-El-Aziz, Michael Knorr, Pierre D. Harvey ClPd(μ-dppm)Cl reacts with (CN-CH-O-CH-) to form the first A-frame-containing organometallic polymer, which is unambiguously characterized with the use of model compounds. This polymer does not experience any weight loss up to 290 °C based on TGA measurements, but DSC traces reveal an irreversible process at 215 °C (DSC). The novel material is also luminescent at 77 K. For example, λ = 660 nm; τ = 0.18 ± 0.01 μs; Φ = 0.0056 (±10%) in PrCN. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: An alternative synthesis of (±)-4-ethynyl[2.2]paracyclophane (PCPh name="tbnd" />CH) (5) and 4,16-diethynyl[2.2]paracyclophane (6) via the Corey–Fuchs reaction has been developed. The olefinic intermediate 4-dibromovinyl[2.2]paracyclophane (3) has been isolated and structurally characterized. The racemic terminal alkyne 5 was employed as starting material for assembling of a luminescent extended π-conjugated system containing a thiophene unit and for a catalytic bis-silylation reaction yielding the olefinic dithioether Z-PhSCH2Me2SiC(H)e2CH2SPh (9). The dimetallatetrahedran [Co2(CO)6(μ-η2–PCP–CCH)] (10) has been prepared and its crystal structure determined by an X-ray diffraction analysis. Alkyne 5 has also been used for the preparation of the Pt(0) complex [Pt(PPh3)2(PCPh name="tbnd" />CH)] (11) and the heterodinuclear dimetallacyclopentenone [(OC)2Fe{μph name="dbnd" />O)C(PCP)3bc;-dppm)Pt(PPh3)] (12). The synthesis and reactivity of 4-isocyano[2.2]paracyclophane (15) towards heterobimetallic iron–platinum and palladium–platinum complexes is also presented. Opening of the dative iron→platinum bond of [(OC)4Fe(μ-dppm)PtCl2] (16) occurred upon addition of 15 to a CH2Cl2 solution of 16 leading to [(OC)4Fe{μ-dppm}PtCl2(Ch name="sbnd" />PCP)] (17). Treatment of [ClPd(μ-dppm)2PtCl] (18) with isocyanide 15 in a 1:1 ratio affords the A-frame compound [ClPd(μ-dppm)2(μ-Ch name="sbnd" />PCP)PtCl] (19), resulting from formal insertion of 15 into the Pd–Pt bond. Addition of 2equiv. of 15–18 leads to the ionic A-frame compound [ClPd(μ-dppm)2(μ-Ch name="sbnd" />PCP)Pt(Ch name="sbnd" />PCP)]Cl (20). [Copyright &y& Elsevier]

The heterodinuclear d9-d9 title compound 1, whose crystal structure has been solved, reacts with dppm [bis(diphenylphosphino)methane] in the presence of NaBF4 to generate the salt [ClPd(μ-dppm)2Pt(Β¹-dppm)][BF4] (2a), which contains a Pt-bound dangling dppm ligand. 2a has been characterized by ¹H and 31P NMR, Fourier transform Raman [ν(Pd-Pt) = 138 cm-1], and UV-vis spectroscopy [λmax(dσ-dσ∗) = 366 nm]. In a similar manner, [ClPd(μ-dppm)2Pt(Β¹-dppm=O)][BF4] (2b), ligated with a dangling phosphine oxide, has been prepared by the addition of dppm=O. The molecular structure of 2b has been established by an X-ray diffraction study. 2a reacts with 1 equiv of NaBH4 to form the platinum hydride complex [(Β¹-dppm)Pd(μ-dppm)2Pt(H)][BF4] (3). Both 2a and 3 react with an excess of NaBH4 to provide the mixed-metal d10-d10 compound [Pd(μ-dppm)3Pt] (4). The photophysical properties of 4 were studied by UV-vis spectroscopy [λmax(dσ-dσ∗) = 460 nm] and luminescence spectroscopy (λemi = 724 nm; τe = 12 ± 1 μs, 77 K). The protonation of 1 and 4 leads to [ClPd(μ-dppm)2(μ-H)PtCl]+ (5) and 3, respectively. Stoichiometric treatment of 1 with cyclohexyl or xylyl isocyanide yields [ClPd(μ-dppm)2Pt(CNC6H11)]Cl (6a) and [ClPd(μ-dppm)2Pt(CN-xylyl)]Cl (6b) ligated by terminal-bound CNR ligands. In contrast, treatment of 1 with the phosphonium salt [C≡NCH2PPh3]Cl affords the structurally characterized A-frame compound [ClPd(μ-dppm)2(μ-C=NCH2PPh3)PtCl]Cl (6c), spanned by a bridging isocyanide ligand. The electrochemical reduction of 2a at -1.2 V vs SCE, as well as the reduction of 5 in the presence of dppm, leads to a mixture of products 3 and 4. Further reduction of 3 at -1.7 V vs SCE generates 4 quantitatively. The reoxidation at 0 V of 4 in the presence of Cl- ions produces back complex 2a. The whole mechanism of the reduction of 1 has been established. [ABSTRACT FROM AUTHOR]

Sol-gel, hydrolytic, non-hydrolytic, self-assembly, catalysis, titanium dioxide, PAHs adsorption, dye-sensitized solar cells (DSSCs), anticorrosion, antifouling, coatings. [Extracted from the article]

A silicalite-1/bismuth composite was synthesized by insertion of liquid bismuth in the 5.5 Å diameter pores of the zeolite under high-pressure, high-temperature conditions. The insertion of bismuth stabilizes the structure with respect to pressure-induced amorphization. Transmission electron microscopy indicated the presence of chains of atoms, which correspond to the 5.5 Å diameter of the host silicalite-1 structure. Neutron powder diffraction also confirmed the insertion of Bi in the pores of silicalite-1. Density functional theory calculations indicate that the insertion of bismuth results in formation of chains with short and long Bi-Bi distances in the pores of the host silicalite-1 linked to the framework by van der Waal's interactions. The material is predicted to be a semiconductor with a band gap of 0.4 eV. Image 1 • Bismuth enters the pores of silicalite-1 under high-pressure, high-temperature conditions. • The Bi-filled silicalite-1 structure is stabilized with respect to pressure-induced amorphization. • DFT results show that Bi atoms form chains with short and long Bi-Bi distances linked to the framework by VDW interactions. • The calculated eDOS show that the Bi-silicalite-1 composite material is a semiconductor with a band gap of 0.4 eV. [ABSTRACT FROM AUTHOR]

Porphyrin–metal conjugates: Some representative examples of peripherally metalated porphyrins are depicted in the graphic. By combining the catalytic, electronic or cytotoxic properties of selected transition‐metal complexes with the binding and electronic properties of porphyrins, enhanced characteristics of the ensemble are generated. Appending one or more transition‐metal complexes to the periphery of porphyrins opens new avenues for potential applications in electron‐ or photon‐triggered catalytic reactions, optoelectronic properties of self‐assembled materials, and therapeutic or diagnostic tools in biomedicine. For more details see the Review by S. Richeter et al. on page 15442 ff. [ABSTRACT FROM AUTHOR]

A porphyrin bearing four imidazolium rings on the meso positions was used as an N-heterocyclic carbene (NHC) precursor for the synthesis of porphyrin dimers with face-to-face orientations. The porphyrins are connected through the formation of eight M–CNHC bonds, with M = AgI or AuI. [ABSTRACT FROM AUTHOR]

Three new tetraphenylethene (TPE) push–pull chromophores exhibiting strong intramolecular charge transfer (ICT) are described. They were obtained via [2 + 2] cycloaddition–retroelectrocyclization (CA-RE) click reactions on an electron-rich alkyne-tetrafunctionalized TPE (TPE-alkyne) using both 1,1,2,2-tetracyanoethene (TCNE), 7,7,8,8-tetracyanoquinodimethane (TCNQ) and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) as electron-deficient alkenes. Only the starting TPE-alkyne displayed significant AIE behavior, whereas for TPE-TCNE, a faint effect was observed, and for TPE-TCNQ and TPE-F4-TCNQ, no fluorescence was observed in any conditions. The main ICT bands that dominate the UV–Visible absorption spectra underwent a pronounced red-shift beyond the near-infrared (NIR) region for TPE-F4-TCNQ. Based on TD-DFT calculations, it was shown that the ICT character shown by the compounds exclusively originated from the clicked moieties independently of the nature of the central molecular platform. Photothermal (PT) studies conducted on both TPE-TCNQ and TPE-F4-TCNQ in the solid state revealed excellent properties, especially for TPE-F4-TCNQ. These results indicated that CA-RE reaction of TCNQ or F4-TCNQ with donor-substituted are promising candidates for PT applications. [ABSTRACT FROM AUTHOR]

The synthesis of phospholyl(borane) amino acids was stereoselectively achieved by reaction of phospholide anion with iodo α-amino ester derived from L-aspartic acid or L-serine, followed by in situ complexation with borane. Phospholyl(borane) amino acids are easy to store and can be subjected to direct transformation into the corresponding free phospholyl, gold complex, oxide or sulfur derivatives as well as phospholinium salts, thus offering a variety of side chains. After selective deprotection of carboxylic function or amine, C- or N-peptide coupling with an alanine moiety proved the possible incorporation into peptides. Such phospholyl amino acid and peptide derivatives exhibit fluorescent properties with a large Stokes shift (160 nm) and fluorescence up to 535 nm, depending on the phosphole aromaticity and the chemical environment. These phospholyl(borane) amino acids constitute a new class of unnatural amino acids useful for structure-activities relationship studies and appear to be promising fluorophores for the development of labeled peptides. [ABSTRACT FROM AUTHOR]

All solid-state dye-sensitized solar cells (ss-DSSCs) based on the reference D102 organic dye and using poly(3-hexylthiophene) ( P3HT ) as hole transporting material were fabricated and compared to the most used 2,2′,7,7′-tetrakis-(N,N-di- p -methoxyphenylamine)-9,9′-spirobifluorene ( spiro-OMeTAD ). Power conversion efficiency of 4.78% was reached with P3HT vs. 3.99% with spiro-OMeTAD , which emphasizes that polythiophene derivatives remain serious alternatives to spiro-OMeTAD for efficient and low-cost photovoltaic energy conversion. Here, P3HT combining high regioregularity, medium-range molecular weight and narrow dispersity was targeted. The ability of those P3HT chains to form semicrystalline domains upon annealing leads to improved hole mobility, photocurrent collection and thus, device performance. [ABSTRACT FROM AUTHOR]

Electronic and steric properties of NHC ligands functionalized with porphyrins were investigated. When porphyrins are used as NHC-wingtips, nickel(II) in the macrocyle significantly improves the catalytic activity of the neighbouring NHC-Rh(I) complex in the conjugate addition of phenylboronic acid to cyclohexen-2-one. [ABSTRACT FROM AUTHOR]

Dynamic covalent polymers (DCPs) offer opportunities as adaptive materials of particular interest for targeting, sensing and delivery of biological molecules. In this view, combining cationic units and fluorescent units along DCP chains is attractive for achieving optical probes for the recognition and delivery of nucleic acids. Here, we report on the design of acylhydrazone-based DCPs combining cationic arginine units with π-conjugated fluorescent moieties based on thiophene-ethynyl-fluorene cores. Two types of fluorescent building blocks bearing neutral or cationic side groups on the fluorene moiety are considered in order to assess the role of the number of cationic units on complexation with DNA. The (chir)optical properties of the building blocks, the DCPs, and their complexes with several types of DNA are explored, providing details on the formation of supramolecular complexes and on their stability in aqueous solutions. The DNA-templated formation of DCPs is demonstrated, which provides new perspectives on the assembly of fluorescent DCP based on the nucleic acid structure. [ABSTRACT FROM AUTHOR]

Synthesis of fluorescent P‐hydroxybinaphtylphosphole‐oxide or ‐sulfide was achieved by trapping a binaphtyl dianion with methyl dichlorophosphite or P‐(N,N‐diethylamino)dichlorophosphine, followed by oxidation or sulfuration of the P‐center. After saponification or acid hydrolysis, the P‐hydroxyphospholes were coupled to peptides using the coupling agent BOP, under the conditions required for the synthesis in solution or on a solid support. This new method was illustrated by the labeling of the JMV2959, a potent antagonist of the Growth Hormone Secretagogue Receptor type 1a (GHS−R1a). The labeled conjugates were used to characterize GHSR ligands by competition assays, based on Fluorescence Resonance Energy Transfer (FRET). Such P‐hydroxyphosphole‐oxide or ‐sulfide constitute a promising new class of compact fluorophores with large Stokes shift, for labeling biomolecules by grafting through the phosphorus atom. [ABSTRACT FROM AUTHOR]

The synthesis, characterization and study of optical properties of innovative tetrafunctionalized zinc(II) porphyrins with carbonic anhydrase (CA) inhibitors in sulfonamide and coumarin series are described. The synthetic methodology relies on the preparation of the porphyrin core by condensation of azido triethyleneglycol functionalized benzaldehyde derivative with pyrrole followed by its metalation and inhibitors coupling via Huisgen click‐reaction. The tetrafunctionalized zinc(II) porphyrin with coumarin moieties showed selective inhibition against tumour‐associated hCA IX and hCA XII versus the cytosolic off‐targets hCA I and hCA II. This compound was able to accumulate on cell membrane and to impair pancreas cancer cells (Capan‐1) proliferation in normoxic conditions with LC50 of 4.5 μM. Moreover, its optical properties revealed efficient photosensitizing properties, leading to cancer cells death under light irradiation, making this compound a suitable candidate for photodynamic therapy. [ABSTRACT FROM AUTHOR]

Abstract: Insertion of aliphatic 1-alkynes such as tert-butylacetylene, 1-hexyne or 1,6-heptadiyne into the Pt–H bond of the heterobimetallic hydride complex [(OC)3Fe{Si(OMe)3}(μ-dppm)Pt(H)(PPh3)] (1) (dppm=Ph2PCH2PPh2) leads to the formation of an isomeric mixture of μ-vinylidene complexes [(OC)3Fe{μ-Cx3bc;-dppm)Pt(PPh3)] (2a: R= tert-Bu, 2b: R= n-Bu, 2c: R=(CH2)3–Cimetallacyclopentenones [(OC)2Fe{μ-C(=O)CRc;-dppm)Pt(PPh3)] (3a: R= tert-Bu, 3b: R= n-Bu, 3c: R=(CH2)3–Cmolecular structures of 2a and 3c have been determined by single-crystal X-ray diffraction. [Copyright &y& Elsevier]

The first synthesis of an original octamer consisting of a central polyhedral oligomeric silsesquioxane (POSS) cage decorated with electro- and optically active arylamine-based push–pull building-blocks is reported herein. Once fully characterized, the potential of the new compound was evaluated as donor material in bulk heterojunction organic solar cells. With promising power conversion efficiencies, good processability and film forming properties, such multimer architectures turns out to be potential candidates to bridge the gap between small molecules and polymers. [ABSTRACT FROM AUTHOR]

Porphyrins and N‐heterocyclic carbenes (NHCs) are both relevant ligands in the fields of coordination and organometallic chemistry. Despite evident structural differences, porphyrins and NHCs have a lot in common such as their ability to form strong metal‐ligand bonds and their use in catalysis, materials science and biomedicine. During the last decade, several molecular systems combining porphyrins and NHC ligands were reported in the literature. The present review gathers relevant examples where NHC ligands are either axially bonded to metalloporphyrins or covalently attached to the porphyrin cores. Structural diversity, electronic interplay between porphyrins and NHCs and some relevant applications in catalysis and biomedicine are notably described. Finally, molecular systems combining NHCs with other original porphyrinoids such as N‐confused porphyrins, subporphyrins and norcorroles are also presented. [ABSTRACT FROM AUTHOR]

Supramolecular polymers are of interest in the pursuit of multivalent nucleic acids recognition. However, their formation often relies on non‐covalent forces that are also at play in the interaction with nucleic acids. In this work, we designed a novel compound (TPE‐Gir) combining a tetraphenylethene aromatic core tethered to four quaternary ammoniums through acylhydrazone spacers, and we investigated in detail its self‐assembly and interaction with different types of nucleic acids. The spectroscopic analyses indicate the self‐assembly of regular fluorescent nanoparticles (observed by DLS and TEM) in the absence of nucleic acids, the strong propensity to intercalate into single‐stranded DNA, the ability to bind into the minor groove of double‐stranded DNA, and the selective binding to G‐quadruplex (G4) structures by fitting within a wide G4‐groove. Those recognition events are quantified by isothermal titration calorimetry and the proposed binding models are supported by docking simulations. [ABSTRACT FROM AUTHOR]

Porphyrins bearing imidazolium salts were synthesized and used as N-heterocylic carbene (NHC) precursors for the preparation of gold(I) complexes. The dark toxicity and phototoxicity of the obtained compounds were investigated in vitro on MCF-7 breast cancer cells. The obtained data showed that porphyrins equipped with imidazolium salts are non-toxic in the dark and present interesting photodynamic properties. On the contrary, corresponding NHC-gold(I) complexes are not suitable photosensitizers for photodynamic therapy (PDT) applications. Their dark toxicity strongly depends on the nature of the linker between the porphyrin core and the NHC. This work was extended to the synthesis of a pyropheophorbide a derivative with a pendant imidazolium group for PDT applications using excitation wavelengths of 450 nm, 545 nm, and importantly of 650 nm. [ABSTRACT FROM AUTHOR]

A series of 2,3-diphenylbuta-1,3-dienes (DPBs) bearing thiophene (T-DPB), bithiophene (BT-DPB) and ethylenedioxythiophene (EDOT-DPB) electropolymerizable units were prepared through desilylation reactions of the corresponding 3,4-diphenylsilole derivatives. These DPB derivatives exhibit remarkably different aggregation induced emission (AIE) or aggregation enhanced emission (AEE) behaviour depending on the strength of the molecular interactions occurring in the solid state. Indeed, T-DPB and EDOT-DPB were found to be good AIEgens while BT-DPB exhibited AEE behaviour. Finally, the electrochemical properties of these new materials were investigated revealing for all DPBs the occurrence of electropolymerization processes leading potentially to low band gap polymers. [ABSTRACT FROM AUTHOR]

High temperature, high pressure conditions were used to insert liquid bismuth in 4–6 nm diameter amorphous silica nanotubes. A combination of transmission electron microscopy and neutron powder diffraction indicate that the final composite consists in 5–6 nm semi-conducting Bi nanowires confined in insulating mesoporous α-quartz. Such a nanostructured material could be of considerable interest for thermoelectric applications. Image 1 • Bismuth was inserted into 4–6 nm silica nanotubes under high-pressure, high-temperature conditions. • The host amorphous nanotubes crystallize in the form of α-quartz. • The obtained nanocomposite consists of 5–6 nm Bi nanowires imbedded in mesoporous α-quartz. • The formation of Bi nanowires modifies their physical properties compared to bulk Bi. [ABSTRACT FROM AUTHOR]

Janus bis(N-heterocyclic carbenes) composed of a porphyrin core with two N-heterocyclic carbene (NHC) heads fused to opposite pyrroles were used as bridging ligands for the preparation of metal complexes. We first focused our attention on the synthesis of gold(I) chloride complexes [(NHC)AuCl] and investigated the substitution of the chloride ligand by acetylides to obtain the corresponding [(NHC)AuC≡CR] complexes. Polyacetylides were then used to obtain molecular multiporphyrinic systems with porphyrins fused to only one NHC ligand, while main-chain organometallic polymers (MCOPs) were obtained when using Janus porphyrin bis(NHCs). Interestingly, MCOPs incorporating zinc(II) porphyrins proved to be efficient as heterogeneous photocatalysts for the generation of singlet oxygen upon visible light irradiation. [ABSTRACT FROM AUTHOR]

• A P3HT-based ABA triblock copolymer containing a perfluoropolyether central segment was synthesized. • Thermal, optical and morphological properties of this ABA triblock copolymer were investigated. • Devices using this triblock copolymer show an almost similar power conversion efficiency to commercial P3HT. A poly(3-hexylthiophene)- block -perfluoropolyether- block -poly(3-hexylthiophene) (P3HT- b -PFPE- b -P3HT) triblock copolymer was synthesized by copper(I)-catalyzed alkyne–azide cycloaddition (CuAAC) in 95% yield. The copolymer was unequivocally characterized by size exclusion chromatography reaching 27 000 g mol−1 and nuclear magnetic resonance (NMR). As expected, diffusion-ordered spectroscopy NMR experiment revealed a lower diffusion coefficient (2.56 × 10-10 m2 s−1) for the P3HT- b -PFPE- b -P3HT triblock copolymer than the ethynyl end-functionalized P3HT (2.83 × 10-10 m2 s−1). Such a triblock copolymer exhibits i) a good thermal stability with no significant weight loss until 320 °C under air, ii) a glass transition of -50 °C due to the soft PFPE segment and iii) a melting peak arising from P3HT at 236 °C. The UV–vis absorption spectrum exhibits a similar absorption profile to that of pure P3HT with a vibronic structure. Analysis of terpolymer thin films by atomic force microscopy imaging and grazing incidence wide-angle X-ray scattering reveals the formation of P3HT crystallites and an "edge-on" orientation of the polymer chains towards the substrate. Preliminary photovoltaic studies on blends of this triblock copolymer combined with a fullerene derivative indicate that the devices using P3HT- b -PFPE- b -P3HT show an almost similar power conversion efficiency to commercial P3HT. [ABSTRACT FROM AUTHOR]

The synthesis of silole amino acids was achieved through hydrosilylation of alkene or alkyne‐containing amino acids with 1‐methyl‐2,3,4,5‐tetraphenyl‐1H‐silole, using Karstedt's catalyst with yield up to 95 % and without epimerization. After selective deprotection of carboxylic acid or amine functions respectively, C‐ or N‐peptide coupling with an alanine moiety proved their possible incorporation into peptides. A model tripeptide was synthesized by solid phase synthesis with the N‐Fmoc protected silole amino acid version. The silole moiety can be also grafted on a precursor peptide directly on the solid support. These amino acids and peptides exhibit AIE properties with λem ca. 500 nm and Δλ ca. 100 nm. This approach constitutes an alternative and promising strategy for incorporation of such AIE fluorogens to peptides. Silole amino acids were obtained by hydrosilylation of unsaturated amino acids with yield up to 95 %. After selective deprotection, C‐ or N‐peptide coupling was performed in solution or on solid support. They exhibit AIE properties (λem ca. 500 nm; Δλ ca. 100 nm) and constitute a promising strategy for incorporation of AIE fluorogens in peptides. [ABSTRACT FROM AUTHOR]

Diazachlorin and diazabacteriochlorin have been prepared through reduction of diazaporphyrin and their in vitro and in vivo activity in photodynamic therapy has been investigated. [ABSTRACT FROM AUTHOR]

Abstract: Periodic mesoporous organosilica nanoparticles emerge as promising vectors for nanomedicine applications. Their properties are very different from those of well‐known mesoporous silica nanoparticles as there is no silica source for their synthesis. So far, they have only been synthesized from small bis‐silylated organic precursors. However, no studies employing large stimuli‐responsive precursors have been reported on such hybrid systems yet. Here, the synthesis of porphyrin‐based organosilica nanoparticles from a large octasilylated metalated porphyrin precursor is described for applications in near‐infrared two‐photon‐triggered spatiotemporal theranostics. The nanoparticles display unique interconnected large cavities of 10–80 nm. The framework of the nanoparticles is constituted with J‐aggregates of porphyrins, which endows them with two‐photon sensitivity. The nanoparticle efficiency for intracellular tracking is first demonstrated by the in vitro near‐infrared imaging of breast cancer cells. After functionalization of the nanoparticles with aminopropyltriethoxysilane, two‐photon‐excited photodynamic therapy in zebrafish is successfully achieved. Two‐photon photochemical internalization in cancer cells of the nanoparticles loaded with siRNA is also performed for the first time. Furthermore, siRNA targeting green fluorescent protein complexed with the nanoparticles is delivered in vivo in zebrafish embryos, which demonstrates the versatility of the nanovectors for biomedical applications. [ABSTRACT FROM AUTHOR]

Cage compounds are very attractive structures for a wide range of applications and there is ongoing interest in finding effective ways to access such kinds of complex structures, particularly those possessing dynamic adaptive features. Here we report the accessible synthesis of new type of organic cage architectures, possessing two different dynamic bonds within one structure: hydrazones and disulfides. Implementation of three distinct functional groups (thiols, aldehydes and hydrazides) in the structure of two simple building blocks resulted in their spontaneous and selective self-assembly into aromatic cage-type architectures. These organic cages contain up to ten components linked together by twelve reversible covalent bonds. The advantage provided by the presented approach is that these cage structures can adaptively self-sort from a complex virtual mixture of polymers or macrocycles and that dynamic covalent chemistry enables their deliberate disassembly through controlled component exchange. [ABSTRACT FROM AUTHOR]

For the first time, POSS-based coordination polymers (CPs) have been structurally characterized. These CPs were obtained in high yield via self-assembly reactions of thioether-functionalized polysilsesquioxanes with CuI salts under mild conditions. Single crystal analyses revealed the formation of 3D networks incorporating different secondary building units (SBUs) as connection nodes. The nature of the -SAr functionality allows a fine-tuning of the cluster nuclearity, that is, butterfly-shaped Cu2X2 or closed cubane-type Cu4I4 cores. As such, the resulting hybrid materials exhibit a combination of high thermal stability arising from the inorganic POSS core along with interesting luminescent properties conferred by the cubane cluster core. Furthermore, the occurrence of channels has been shown crystallographically in the case of the Cu4I4 cluster containing CP. [ABSTRACT FROM AUTHOR]

Porphyrins fused to imidazolium salts across two neighboring β-pyrrolic positions were used as N-heterocyclic carbene (NHC) precursors to anchor AuI-Cl complexes at their periphery. Synthesis of several thiolato-AuI complexes was then achieved by substituting chloride for thiolates. Photodynamic properties of these complexes were investigated: the data obtained show that the Au−S bonds could be cleaved upon irradiation. The proposed mechanism to explain the release of thiolate moiety involves the S atom oxidation by singlet oxygen generated in the course of irradiation. In view of photodynamic therapy (PDT) applications, these porphyrins fused to NHC-AuI complexes were tested as photosensitizers to kill MCF-7 breast cancer cells. Results show the important role played by the ancillary ligands (chloride versus thiolates) on the photodynamic effect. [ABSTRACT FROM AUTHOR]

Background: Genomic selection (GS) uses information from genomic signatures consisting of thousands of genetic markers to predict complex traits. As such, GS represents a promising approach to accelerate tree breeding, which is especially relevant for the genetic improvement of boreal conifers characterized by long breeding cycles. In the present study, we tested GS in an advanced-breeding population of the boreal black spruce (Picea mariana [Mill.] BSP) for growth and wood quality traits, and concurrently examined factors affecting GS model accuracy. Results: The study relied on 734 25-year-old trees belonging to 34 full-sib families derived from 27 parents and that were established on two contrasting sites. Genomic profiles were obtained from 4993 Single Nucleotide Polymorphisms (SNPs) representative of as many gene loci distributed among the 12 linkage groups common to spruce. GS models were obtained for four growth and wood traits. Validation using independent sets of trees showed that GS model accuracy was high, related to trait heritability and equivalent to that of conventional pedigree-based models. In forward selection, gains per unit of time were three times higher with the GS approach than with conventional selection. In addition, models were also accurate across sites, indicating little genotype-by-environment interaction in the area investigated. Using information from half-sibs instead of full-sibs led to a significant reduction in model accuracy, indicating that the inclusion of relatedness in the model contributed to its higher accuracies. About 500 to 1000 markers were sufficient to obtain GS model accuracy almost equivalent to that obtained with all markers, whether they were well spread across the genome or from a single linkage group, further confirming the implication of relatedness and potential longrange linkage disequilibrium (LD) in the high accuracy estimates obtained. Only slightly higher model accuracy was obtained when using marker subsets that were identified to carry large effects, indicating a minor role for short-range LD in this population. Conclusions: This study supports the integration of GS models in advanced-generation tree breeding programs, given that high genomic prediction accuracy was obtained with a relatively small number of markers due to high relatedness and family structure in the population. In boreal spruce breeding programs and similar ones with long breeding cycles, much larger gain per unit of time can be obtained from genomic selection at an early age than by the conventional approach. GS thus appears highly profitable, especially in the context of forward selection in species which are amenable to mass vegetative propagation of selected stock, such as spruces. [ABSTRACT FROM AUTHOR]

Brillouin spectroscopy is used to investigate the elastic properties of XAlSiO 4 aluminosilicate glasses where X = Li, Na, K, Mg 0.5 , Ca 0.5 , Sr 0.5 , Ba 0.5 , and Zn 0.5 . The Brillouin frequency shifts obtained in two different scattering geometries allow the calculation of the refractive index, the two sound velocities and Poisson's ratio. Measurements of the mass density give in turn the elastic moduli and the Debye temperature. We find that the elastic properties scale with the atomic density of the glassy network or the charge-balancing cation field strength while they negatively correlate with the glass transition temperature. Further, Poisson's ratio depends on the nature of the non-framework cations in this glass series. [ABSTRACT FROM AUTHOR]

The reactivity of benzimidazol-2-ylidenes with respect to gold nanoparticles (AuNPs) has been investigated using a combined experimental and computational approach. First, the grafting of benzimidazol-2-ylidenes bearing benzyl groups on the nitrogen atoms is described, and comparisons are made with structurally similar N-heterocyclic carbenes (NHCs) bearing other N-groups. Similar reactivity was observed for all NHCs, with 1) the erosion of the AuNPs under the effect of the NHC and 2) the formation of bis(NHC) gold complexes. DFT calculations were performed to investigate the modes of grafting of such ligands, to determine adsorption energies, and to rationalize the spectroscopic data. Two types of computational models were developed to describe the grafting onto large or small AuNPs, with either periodic or cluster-type DFT calculations. Calculations of NMR parameters were performed on some of these models, and discussed in light of the experimental data. [ABSTRACT FROM AUTHOR]

Porphyrins fused to peripheral N-heterocyclic carbenes (NHC) across two neighboring β,β-pyrrolic positions were used for the synthesis of different mono- and bis-carbenic gold(I) complexes. These studies also revealed how it is possible to modulate the reactivity of the peripheral NHC by deprotonating the inner NH groups of the fused free base porphyrin core. All complexes were fully characterized and displayed high stability, allowing the formation of mono-carbenic and also stable homoleptic and heteroleptic bis-carbenic Au(I) complexes. Optical and electrochemical properties of bis-carbenic Au(I) revealed no or weak electronic communication between the porphyrins, which behave as two independent groups. [ABSTRACT FROM AUTHOR]

Conjugated poly(3-hexylthiophene) copolymer derivatives containing 10% appended porphyrin moieties are prepared using a supramolecular approach toward applications in organic electro­nics. The self-assembled polythiophene-porphyrin copolymers are synthesized by coordination of the porphyrinato central zinc ions to the imidazole-functionalized polythiophene side chains. Evidence for the self-assembly process is provided by 1H NMR spectroscopy, single crystal X-ray diffraction, and optical absorption studies on model compounds. The polythiophene-porphyrin copolymers show an extended absorption window in the region of 420-650 nm due to the contribution of the porphyrin. Photoluminescence studies indicate concentration-dependent energy transfer from P3HT to the porphyrin. Preliminary photovoltaic studies are performed by combining the polythiophene-porphyrin copolymers with PC61BM in the photo­active layer of bulk heterojunction organic solar cells. [ABSTRACT FROM AUTHOR]

Poly(3-hexylthiophene)s end-functionalized with π-extended porphyrins have been synthesized in a one-pot procedure. The polymers show a broad absorption profile extending to 700 nm and a fibrillar microstructure, which can be tuned through judicious selection of the porphyrin molar ratio. [ABSTRACT FROM AUTHOR]

Porphyrins fused to N -heterocyclic carbenes (NHCs) 1M , with inner metal M = Ni, Cu, Zn and H2, were used to synthesize palladium(II) complexes. These complexes behaved as precatalysts for high-temperature Mizoroki–Heck reactions between iodobenzene and styrene. Despite similar electronic properties between 1M ligands, catalytic activity was found to significantly depend on the presence, or not, of a central metal incorporated in the porphyrin core: a conversion of iodobenzene between 80–90% was observed with metalloporphyrins (M = Ni, Cu and Zn), whereas only 30% was observed with free-base porphyrins (M = H2) after 10 h. Palladium leaching and subsequent trapping of free palladium in the inner core of the free-base porphyrin modified the concentration of Pd(0) active species and may explain the lower catalytic activity observed. [ABSTRACT FROM AUTHOR]

Subcritical crack growth and crack closure are analysed using the double cleavage drilled compression method, in two calcium phosphate-based glasses. The measurements of the crack velocity as a function of temperature, from ambient to 250 °C, are reported for two different relative humidity levels. Studied glasses present unusual trends characterized by a non-gradual shift of V- K curves versus temperature. Moreover, when the load is released and crack closes, expulsion of a 'liquid-like' phase is observed forming droplets along the crack path. These droplets are only formed at certain temperatures, but both under high and low water humidity. They evolve towards residues when temperature is decreased. [ABSTRACT FROM AUTHOR]

Hybrid organic–inorganic proton conducting membranes based on arylsulfonic acid (Ar-SO 3 H) groups and poly(ethylene glycol) (PEG) units were easily obtained in one step synthesis by co-hydrolysis and polycondensation of 2-(4-Chlorosulfonylphenyl)ethyl trimethoxysilane and bis-silylated polyethylene oxide. The hydrolysis of SO 2 Cl groups into SO 3 H was achieved during the sol–gel process by the in situ generated HCl acting as catalyst for the hydrolysis and polycondensation reactions. All membranes were characterized by 1 H, 13 C and 29 Si MAS solid-state NMR, elementary analysis, Scanning Electron Microscopy (SEM) and X-ray photoelectron (XPS) spectroscopy. Their thermal and thermomechanical properties were investigated by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA), respectively.. The thermomechanical and conductive properties were found to be dependent on the PEG chain length and the PMMA amount. The proton conductivities of these materials were found to be approximately 10 −2 S cm −1 at 20 °C. [ABSTRACT FROM AUTHOR]

TiO2/conjugated polymersare promising materials insolar energy conversion where efficient photoinduced charge transfersare required. Here, a “grafting-from” approach for thesynthesis of TiO2nanoparticles supported with conjugatedpolymer brushes is presented. Poly(3-hexylthiophene) (P3HT), a benchmarkmaterial for organic electronics, was selectively grown from TiO2nanoparticles by surface-initiated Kumada catalyst-transferpolycondensation. The grafting of the polymer onto the surface ofthe TiO2nanoparticles by this method was demonstratedby 1H and 13C solid-state NMR, X-ray photoelectronspectrometry, thermogravimetric analysis, transmission electron microscopy,and UV–visible spectroscopy. Sedimentation tests in tetrahydrofuranrevealed improved dispersion stability for the TiO2@P3HThybrid material. Films were produced by solvent casting, and the qualityof the dispersion of the modified TiO2nanoparticles wasevaluated by atomic force microscopy. The dispersion of the P3HT-coatedTiO2NPs in the P3HT matrix was found to be homogeneous,and the fibrillar structure of the P3HT matrix was maintained whichis favorable for charge transport. Fluorescence quenching measurementson these hybrid materials in CHCl3indicated improved photoinducedelectron-transfer efficiency. All in all, better physicochemical propertiesfor P3HT/TiO2hybrid material were reached via the surface-initiated“grafted-from” approach compared to the “grafting-onto”approach. [ABSTRACT FROM AUTHOR]

Aromatic nucleophilic substitution reaction of the nitro group of meso-nitroporphyrins with azide and various amines was achieved and represents an alternative procedure to C-N coupling reactions usually needed to obtain such meso-N-substituted porphyrins in good yields. [ABSTRACT FROM AUTHOR]

Meso-structured and ladder organic-inorganic hybrid materials functionalized with ammonium carboxylate groups were prepared. These materials were obtained by the sol-gel process starting from the cyanopropyltriethoxysilane precursor as a building block. Hydrolysis of CN to COOH groups followed by treatment with triethylamine gives rise to cationic exchange materials. These materials exhibit a high chelating capability towards cations and can be used for water treatment. Lead ion (Pb) was tested as example; and, some tests were made on the meso-structured and ladder material for further comparison in efficacy of extractions. [ABSTRACT FROM AUTHOR]