The rapid growth of plastics production exacerbated the triple planetary crisis of habitat loss, plastic pollution and greenhouse gas (GHG) emissions. Circular strategies have been proposed for plastics to achieve net-zero GHG emissions. However, the implications of such circular strategies on absolute sustainability have not been examined on a planetary scale. This study links a bottom-up model covering both the production and end-of-life treatment of 90% of global plastics to the planetary boundaries framework. Here we show that even a circular, climate-optimal plastics industry combining current recycling technologies with biomass utilization transgresses sustainability thresholds by up to four times. However, improving recycling technologies and recycling rates up to at least 75% in combination with biomass and CO2 utilization in plastics production can lead to a scenario in which plastics comply with their assigned safe operating space in 2030. Although being the key to sustainability and in improving the unquantified effect of novel entities on the biosphere, even enhanced recycling cannot cope with the growth in plastics demand predicted until 2050. Therefore, achieving absolute sustainability of plastics requires a fundamental change in our methods of both producing and using plastics.

A methodology for the synthesis of 2H‐[1,3]oxazino[3,2‐α]indolin‐4(3H)‐ones is reported. They are obtained from readily available materials by a facile synthetic procedure following either a two‐step cascade reaction or a step‐by‐step transformation. The target compounds represent a hitherto unreported class of indole derivatives with a novel kind of tris‐ or tetracyclic backbone.

The combination of cinchona-alkaloid-derived primary amine and AuI–phosphine catalysts allowed the selective C–H functionalization of two adjacent carbon atoms of pyrroles under mild reaction conditions. This sequential dual activation provides seven-membered-ring-annulated pyrrole derivatives in excellent yields and enantioselectivities.

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This methodology-oriented review covers the synthetic strategies to construct seven-membered carbocycles in naturally occurring compounds over the last ten years. It offers an insight into the common synthetic targets and approaches and provides useful information for further developments within this area of natural product synthesis as well as synthetic methodology in general.