No abstract

No abstract

In this work, we study the synthesis of diphenyl carbonate (DPC) from phenol and CO on gold electrodes studied by means of in situ Fourier transform infrared spectroscopy (FTIR). The results show that, on gold electrodes, the formation of DPC is observed at potentials as low as 0.4 V vs Ag/AgCl, together with the formation of dimethyl carbonate (DMC) from the carbonylation of methanol that was used as a solvent. The spectroelectrochemical results also suggest that the formation of DPC occurs via the replacement of the methoxy groups from DMC with phenoxy groups from phenol and not directly by the carbonylation of phenol. Although this transesterification process is known to occur with heterogeneous catalysts, it has not been reported under electrochemical conditions. These are interesting findings, since the direct DPC production by carbonylation of phenol to DPC is usually performed with Pd-based catalysts. With this reaction scheme of transesterification happening under electrochemical conditions, other non-Pd catalysts could be used as well for one-step DPC production from phenol and CO. These findings give important mechanistic insights into this reaction and open up possibilities to an alternative process for the production of DPC.

Organic carbonates are an important source for polycarbonate synthesis. However, their synthesis generally requires phosgene, sophisticated catalysts, harsh reaction conditions, or other highly reactive chemicals. We present the first direct electrochemical generation of mesityl methyl carbonate by C–H activation. Although this reaction pathway is still challenging concerning scope and efficiency, it outlines a new strategy for carbonate generation.

Summary:The chemical industry has set ambitious targets for the reduction of greenhouse gas emissions and energy consumption. In the present work, a systematic approach for a successful reduction of energy consumption and emissions is presented. A Structured Efficiency System for Energy (STRUCTese 1 ) helps to identify, monitor and manage energy efficiency. The method fosters and accompanies energy saving measures as shown in the first two examples from polymer production: energy savings through operational efficiency and raw material savings with a new plant design. In addition, such a systematic approach pushes the development of innovative processes and provides a vision for an energy efficient future as shown in the third example: the use of CO 2 as a raw material in the copolymerization with epoxides.