Total Synthesis of (15R)- and (15S)-Prostaglandin A.

From both pharmaceutical and structural perspectives, the large family of prostaglandins represent a truly remarkable class of natural products. Prostaglandin A is a tissue hormone naturally found in human seminal plasma and in the sea whip Plexaura homomalla with yet poorly understood biological or therapeutic effects. Herein, a novel strategy for the stereoselective construction of both naturally occurring prostaglandin A epimers and first insights into their functional effects on the major inhibitory neurotransmitter γ-aminobutyric acid (GABA) type A receptors (GABAR) are provided.

Chemical Recycling of End-of-Life Poly(lactide) via Zinc-Catalyzed Depolymerization and Polymerization.

The chemical recycling of poly(lactide) was investigated based on depolymerization and polymerization processes. Using methanol as depolymerization reagent and zinc salts as catalyst, poly(lactide) was depolymerized to methyl lactate applying microwave heating. An excellent performance was observed for zinc(II) acetate with turnover frequencies of up to 45000 h.

Chemical Recycling of End-of-Life Poly(lactide) via Zinc-Catalyzed Depolymerization and Polymerization.

10.1002/open.202000243.

Hydrogenative Depolymerization of End-of-Life Polycarbonates by an Iron Pincer Complex.

Chemical recycling processes can contribute to a resource-efficient plastic economy. Herein, a procedure for the iron-catalyzed hydrogenation of the carbonate function of end-of-life polycarbonates under simultaneous depolymerization is presented. The use of a straightforward iron pincer complex leads to high rate of depolymerization of poly(bisphenol A carbonate) and poly(propylene carbonate) yielding the monomers bisphenol A and 1,2-propanediol, respectively, as products under mild reaction conditions.

Ruthenium-Catalyzed Hydrogenative Degradation of End-of-Life Poly(lactide) to Produce 1,2-Propanediol as Platform Chemical.

The chemical recycling of end-of-life polymers can add some value to a future circular economy. In this regard, the hydrogenative degradation of end-of-life PLA was investigated to produce 1,2-propanediol as product, which is a useful building block in polymer chemistry. In more detail, the commercially available Ru-MACHO-BH complex was applied as catalyst to degrade end-of-life PLA efficiently to 1,2-propanediol under mild conditions.

Hydrogenative Depolymerization of End-of-Life Poly-(Bisphenol A Carbonate) Catalyzed by a Ruthenium-MACHO-Complex.

The valorization of waste to valuable chemicals can contribute to a more resource-efficient and circular chemistry. In this regard, the selective degradation of end-of-life polymers/plastics to produce useful chemical building blocks can be a promising target. We have investigated the hydrogenative depolymerization of end-of-life poly(bisphenol A carbonate).

Recycling of End-of-Life Poly(bisphenol A carbonate) via Alkali Metal Halide-Catalyzed Phenolysis.

The chemical recycling of end-of-life plastic waste streams can contribute to a resource-conserving and sustainable society. This matter of recycling is composed of a sequence of depolymerization and subsequent polymerization reactions. In this regard, we have studied the chemical recycling of end-of-life poly(bisphenol A carbonate) applying phenol as depolymerization reagent.