58 research outputs found
Photochemical Upcycling/Modification of Polystyrene-based Plastic Waste
The escalating accumulation of plastic waste in landfills and marine environments has become a pressing concern to society. Among all plastic-based waste, polystyrenes are widely utilized as a commodity plastic and present very low recyclability. To improve this scenario, photocatalysis has recently become one of the viable techniques which can be performed under mild conditions. In this concise review, we have highlighted recent advancements in the valorization of polystyrene-based plastic waste by mainly focusing on the selective functionalization of the C–H bonds. This strategy clearly holds strong promise for the sustainable and efficient conversion of polystyrene-based waste and contributes to the reduction of waste and resource conservation
Synthesis of cyclic carbonates from diols and CO2 catalyzed by carbenes
The synthesis of cyclic carbonates from epoxides and CO2 is a well-established reaction, whereas the synthesis of cyclic carbonates from diols and CO2 is considerably more challenging, and few efficient catalysts are available. Here, we describe heterocyclic carbene catalysts, including one derived from a cheap and efficient thiazolium salt, for this latter reaction. The reaction proceeds at atmospheric pressure in the presence of an alkyl halide and Cs2CO3. Reaction mechanisms for the transformations involved are also proposed
Thiazolium carbene catalysts for the fixation of CO2 onto amines
The catalytic N-formylation and N-methylation of amines using CO2 as the carbon source represents a facile and sustainable approach for the synthesis of pharmaceuticals and natural products. Herein, we describe highly effective and inexpensive thiazolium carbene-based catalysts derived from vitamin B1 for the N-formylation and N-methylation of amines, using polymethylhydrosiloxane (PMHS) as a reducing agent, which operate under ambient conditions
Photochemical upcycling/modification of polystyrene-based plastic waste
Abstract: The escalating accumulation of plastic waste in landfills and marine environments has become a pressing concern to society. Among all plastic-based waste, polystyrenes are widely utilized as a commodity plastic and present very low recyclability. To improve this scenario, photocatalysis has recently become one of the viable techniques which can be performed under mild conditions. In this concise review, we have highlighted recent advancements in the valorization of polystyrene-based plastic waste by mainly focusing on the selective functionalization of the C-H bonds. This strategy clearly holds strong promise for the sustainable and efficient conversion of polystyrene-based waste and contributes to the reduction of waste and resource conservation
Recent advances on the carboxylations of C(sp\ub3)-H bonds using CO\u2082 as the carbon source
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