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A series of porous organic polymers based on a singlet oxygen generating oxoporphyinogen ('OxP') has been successfully prepared from a pseudotetrahedral OxP-tetraamine precursor (OxP(4-NH2Bn)4) by its reaction with tetracarboxylic acid dianhydrides under suitable conditions. Of the compounds studied, those containing naphthalene (OxP-N) and perylene (OxP-P) spacers, respectively, have large surface areas (~530 m2 g−1). On the other hand, the derivative with a simple benzene spacer (OxP-B) exhibits the best 1O2 generating capability. Although the starting OxP-tetraamine precursor is a poor 1O2 generator, its incorporation into OxP POPs leads to a significant enhancement of 1O2 productivity, which is largely due to the transformation of NH2 groups to electron-withdrawing diimides. Overall 1O2 production efficacy of OxP-POPs under irradiation by visible light is significantly improved over the common reference material PCN-222. All the materials OxP-B, OxP-N and OxP-P promote oxidation of thioanisole involving conversion of ambient triplet state oxygen to singlet oxygen under visible light irradiation and its reaction with the sulfide. Although the reaction rate of the oxidation promoted by OxP POPs is generally lower than for conventional materials (such as PCN-222) or previously studied OxP derivatives, undesired overoxidation of the substrate to methyl phenyl sulfone is suppressed. For organic sulfides, selectivity of oxidation is especially important for detoxification of mustard gas (bis(2-chloroethyl)sulfide) or similarly toxic compounds since controlled oxidation leads to the low toxicity bis(2-chloroethyl)sulfoxide while overoxidation leads to intoxification (since bis(2-chloroethyl)sulfone presents greater toxicity to humans than the sulfide substrate). Therefore, OxP POPs capable of promoting selective oxidation of sulfides to sulfoxides have excellent potential to be used as mild and selective detoxification agents. IMPACT STATEMENT: Oxoporphyrinogen (OxP) is a unique chromophore compound in that it is intrinsically de-aggregated allowing large quantum yields of singlet oxygen generation. Due to its structure, OxP is also an ideal building block for porous systems. In this work, we describe the first incorporation of OxP in highly stable microporous polymers strongly enhanced singlet oxygen generation for selective oxidation of organic sulfides to sulfoxides (as a model reaction) under heterogeneous conditions. The novelty of this work lies in the high stability and easy recovery of the materials, the synergetic enhancement of singlet oxygen generation in the polymers over the starting OxP, and the excellent selectivity for the oxidation reaction. [ABSTRACT FROM AUTHOR]

A series of mononuclear ruthenium(II) tetra-tert-butyl-phthalocyaninates bearing axial N-donor ligands [tBu4PcRu]L2 (L = trimethylamine, pyrazine, 4,4′-bipyridine and N-methyl-4,4′-bipyridinium iodide) as well as the binuclear complex [tBu4PcRu]2(BiPy)3 were synthesized starting from the complex with axially coordinated carbonyl group [tBu4PcRu](CO). All compounds have been characterized by NMR, UV-Vis and cyclic voltammetry. The latter allowed the determination of oxidation and reduction potentials, HOMO-LUMO gaps and revealed the possibility of electropolymerization of BiPy-containing complexes in clear contrast to complexes containing another bidentate ligand – pyrazine. Comparative electrochemical studies of the mono- and binuclear complexes [tBu4PcRu](BiPy)2 and [tBu4PcRu]2(BiPy)3 revealed that the phthalocyanine rings are not conjugated in the binuclear species. The remarkable dependence of singlet oxygen generation from axial ligands in ruthenium phthalocyaninates was observed: the complexes with carbonyl group [tBu4PcRu](CO) and with pyrazine molecules [tBu4PcRu](Pyz)2 show higher 1O2 quantum yields, whereas the complex with axially coordinated molecules of trimethylamine [tBu4PcRu](NMe3)2 and quaternized BiPy ligands [tBu4PcRu](BiPy-Me+)2 have the lowest ability to generate singlet oxygen. The revealed influence of axial ligands on key physicochemical properties paves the way for the design of new ruthenium phthalocyaninates with potential optoelectronic and biomedical applications. [ABSTRACT FROM AUTHOR]

A novel asymmetric Zn (II) phthalocyanine (Pcs) (5) peripherally substituted with one cyclotriphosphazene ring and six tert-butylphenoxy groups was synthesized and fully characterized by elemental analysis, mass, 1H, 13C, 31P NMR, and FT-IR spectroscopies. Photophysical and photochemical properties of 5 (ground state absorption, fluorescence emission, fluorescence lifetime, fluorescence quantum yield, and singlet oxygen generation) were investigated in DMSO and THF. The determined singlet oxygen quantum yields of compound 5 in DMSO and THF were 0.62 and 0.52, respectively. These singlet oxygen quantum yields are very near the singlet oxygen quantum yield of unsubstituted Zn(II) Pcs used as the reference compound. This new Zn(II) Pcs may be a promising candidate for photodynamic therapy (PDT) with its photophysical and photochemical properties. [ABSTRACT FROM AUTHOR]

Star-shaped porphyrin-cored poly(l-lactide)-b-poly(lactobionamidoethyl methacrylate) block copolymers (SPPLA-b-PLAMA) were synthesized via RAFT of unprotected Lactobionamidoethyl methacrylate (LAMA) in 1-methyl-2-pyrrolidinone (NMP) solution at 70 °C. The structure of this as-synthesized SPPLA-b-PLAMA block copolymer was thoroughly studied by nuclear magnetic resonance spectroscopy, gel permeation chromatography (GPC), and Fourier transforms infrared. Moreover, under the irradiation, such SPPLA-b-PGAMA copolymer exhibits efficient singlet oxygen generation (0.17) and indicates high fluorescence quantum yields (0.20). Notably, with UV–vis investigation, SPPLA-b-PLAMA showed a very specific recognition with RCA120lectin. This will not only provide potentially prophyrin-cored star-shaped SPPLA-b-PLAMA block copolymers for targeted photodynamic therapy, but also improve the physical, biodegradation, biocompatibility properties of PLA-based biomaterials. [ABSTRACT FROM AUTHOR]