In an aspect, a plurality of artificial melanin nanoparticles are provided, wherein: each melanin nanoparticle of the plurality of artificial melanin nanoparticles comprises a plurality of melanin oligomers; each melanin oligomer comprises a plurality of covalently-bonded melanin base units; and each melanin base unit comprises substituted or unsubstituted naphthalene. In an aspect, porous artificial melanin materials and methods of synthesizing porous artificial melanin materials are provided.

The disclosure relates to dicarbonyl complexes of ruthenium and osmium with bi- and tridentate nitrogen and phosphine ligands. The disclosure relates to methods for preparing these complexes and the use of these complexes, isolated or prepared in situ, as catalysts for reduction reactions of ketones and aldehydes both via transfer hydrogenation or hydrogenation with hydrogen.

The disclosure relates to dicarbonyl complexes of ruthenium and osmium with bi- and tridentate nitrogen and phosphine ligands. The disclosure relates to methods for preparing these complexes and the use of these complexes, isolated or prepared in situ, as catalysts for reduction reactions of ketones and aldehydes both via transfer hydrogenation or hydrogenation with hydrogen.

Metal-organic frameworks (MOFs) and method of using the MOFs to catalyze reactions involving epoxide ring-opening mechanisms are provided. The structure of the MOFs can be represented by the formula: M.sub.6(μ.sub.3-ligand).sub.8(OH.sub.x).sub.8(TBAPy).sub.2, where M is Zr or Hf, the ligands are selected from hydroxo-, oxo- and aquo-ligands, and x is independently selected from 1 or 2.

Metal-organic frameworks (MOFs) and method of using the MOFs to catalyze reactions involving epoxide ring-opening mechanisms are provided. The structure of the MOFs can be represented by the formula: M.sub.6(μ.sub.3-ligand).sub.8(OH.sub.x).sub.8(TBAPy).sub.2, where M is Zr or Hf, the ligands are selected from hydroxo-, oxo- and aquo-ligands, and x is independently selected from 1 or 2.

The present invention concerns a method for depolymerizing oxygenated polymer materials and the use of said method in the recycling of plastic materials and the preparation of aromatic compounds that can be used as fuel, synthesis intermediates and raw materials in the construction sectors and in the petrochemical, electrical, electronic, textile, aeronautical, pharmaceutical, cosmetics and agrochemical industries. The present invention also concerns the use of aromatic compounds obtained by the method for depolymerizing oxygenated polymer materials according to the invention, in the production of fuels, electronic components, plastic polymers, rubber, drugs, vitamins, cosmetic products, perfumes, food products, synthetic threads and fibres, synthetic leathers, glues, pesticides and fertilizers.

The present invention concerns a method for depolymerizing oxygenated polymer materials and the use of said method in the recycling of plastic materials and the preparation of aromatic compounds that can be used as fuel, synthesis intermediates and raw materials in the construction sectors and in the petrochemical, electrical, electronic, textile, aeronautical, pharmaceutical, cosmetics and agrochemical industries. The present invention also concerns the use of aromatic compounds obtained by the method for depolymerizing oxygenated polymer materials according to the invention, in the production of fuels, electronic components, plastic polymers, rubber, drugs, vitamins, cosmetic products, perfumes, food products, synthetic threads and fibres, synthetic leathers, glues, pesticides and fertilizers.

A method includes depolymerizing post-consumer or post-industrial recycled polyethylene terephthalate (rPET) to form bis(2-hydroxyethyl) terephthalate (BHET), and reacting at least a portion of the BHET with a catalyst to form an alcohol. The alcohol includes cyclohexanedimethanol (CHDM) or 1,4-phenylenedimethanol (PDM). Further steps of the method include polymerizing the alcohol in the presence of additional BHET to form a polyester. The polyester may include poly(cyclohexylenedimethylene terephthalate (PCT), polyethylene terephthalate glycol (PETG) copolyester, polycyclohexylene dimethylene terephthalate glycol (PCTG) copolyester, polycyclohexylene dimethylene terephthalate acid (PCTA), or a monomer having repeating units with the structure (I), wherein n is an integer having a value of at least 20.

##STR00001##

A method includes depolymerizing post-consumer or post-industrial recycled polyethylene terephthalate (rPET) to form bis(2-hydroxyethyl) terephthalate (BHET), and reacting at least a portion of the BHET with a catalyst to form an alcohol. The alcohol includes cyclohexanedimethanol (CHDM) or 1,4-phenylenedimethanol (PDM). Further steps of the method include polymerizing the alcohol in the presence of additional BHET to form a polyester. The polyester may include poly(cyclohexylenedimethylene terephthalate (PCT), polyethylene terephthalate glycol (PETG) copolyester, polycyclohexylene dimethylene terephthalate glycol (PCTG) copolyester, polycyclohexylene dimethylene terephthalate acid (PCTA), or a monomer having repeating units with the structure (I), wherein n is an integer having a value of at least 20.

##STR00001##

The present invention relates to kinetic resolution of racemic δ-hydroxyl ester via asymmetric catalytic hydrogenation and an application thereof. In the presence of chiral spiro pyridyl phosphine ligand Iridium catalyst and base, racemic δ-hydroxyl esters were subjected to asymmetric catalytic hydrogenation to obtain extent optical purity chiral δ-hydroxyl esters and corresponding 1,5-diols. The method is a new, efficient, highly selective, economical, desirably operable and environmentally friendly method suitable for industrial production. An optically active chiral δ-hydroxyl ester and 1,5-diols can be obtained at very high enantioselectivity and yield with relatively low usage of catalyst. The chiral δ-hydroxyl ester and 1,5-diols obtained by using the method can be used as a critical raw material for asymmetric synthesis of chiral drugs (R)-lisofylline and natural drugs (+)-civet, (−)-indolizidine 167B and (−)-coniine.