Porous organic polymers (POPs), a class of highly crosslinked amorphous polymers possessing nano-pores, have recently emerged as a versatile platform for the deployment of catalysts. The bottom-up approach for porous organic polymer synthesis provides the opportunity for the design of polymer frameworks with various functionalities, for their use as catalysts or ligands. This tutorial review focuses on the framework structures and functionalities of catalytic POPs. Their structural design, functional framework synthesis and catalytic reactions are discussed along with some of the challenges.

The use of carbon dioxide as a renewable and environmentally friendly source of carbon is highly attractive. This article focuses on recent developments in important new reactions and new catalysts for homogeneous CO₂ transformations under mild reaction conditions. Other than traditional organometallic catalysts, organocatalysts have also been applied in the chemical conversion of CO₂ and have demonstrated very promising ability in this field. As the coupling of epoxides with CO₂ to form cyclic carbonates or polycarbonates has been well documented, it will be excluded from this article.

5-Hydroxymethylfurfural (HMF) has been known as a product from hexose dehydration for over 100 years and is considered to be one of the most promising platform molecules that can be converted into a variety of interesting chemicals. HMF, together with furfural and 2,5-furandicarboxylic acid (FDCA) are derivatives of furan compounds, which were listed as the top 10 value-added bio-based chemicals by the US Department of Energy. The great and increasing interest in the production of furan derivatives from biomass resources is due to the great potential of furan derivatives as feedstock for bulk chemicals and fuels. HMF can be synthesized by dehydration of all types of C6 carbohydrates, including monomeric and polymeric carbohydrates, such as fructose, glucose, sucrose, starch, inulin, cellulose, and raw biomass. Numerous improvements and milestones have been made in the dehydration process during the past 130 years. The big challenge for the process of HMF production is its suitability for industrial scale yet being cost efficient. This perspective article will review the HMF development timeline, focusing on the important events, landmark contributions, engineering and practical challenges of HMF production.