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A highly efficient and environmentally friendly approach for the synthesis of 1,8-dioxo- octahydroxanthenes has been developed catalysed by a supported cobalt nanoparticle catalyst (CoNP@SBA-15) in water. The use of this heterogeneous catalytic system offered several advantages including high yields, low catalyst loading, short reaction times and easy workup. Furthermore, the catalyst was efficiently reused for ten consecutive cycles without any significant loss in catalytic activity.

Zn-Co double metal cyanide (DMC) catalysts were prepared by varying the initial amounts of ZnCl2 to analyze the influence of method of preparation on the different copolymerization parameters. Synthesized catalysts were analyzed by different techniques, infrared spectrometry and inductively coupled plasma optical emission spectrometry, scanning electron microscopy, N2-physisorption and X-ray diffraction to determine whether characteristics affect the catalytic activity. The copolymers were characterized by infrared spectrometry and gel permeation chromatography. Highly active catalyst (2.5 kg polymer/g catalyst) was synthesized, low amounts of cyclic carbonate byproduct were produced (0.4 %) with medium crystallinity catalysts and considerable amounts of K+ (0.4% to 1.0%wt)., CTQ2015-64892-R (MINECO/FEDER)