Integrated electrochemical CO 2 reduction and hydroformylation

The development of integrated multi-catalyst processes has become of high interest to transform abundant feedstocks or environmental pollutants to commodity chemicals in a one pot, one pass fashion. Specifically, CO poses a large environmental burden and would thus be a desirable, relatively abundant C1 source in multi-step synthetic chemistry. Herein we disclose the synthesis of aldehydes from CO the integration of electrochemical CO reduction (CO RR) and hydroformylation, taking advantage of the typically unwanted concomitant hydrogen evolution (HER) to generate the necessary CO and H needed for hydroformylation. Though typical hydroformylation catalysts based on Rh would be deactivated under CO RR conditions, we circumvent this limitation by spatially segregating our CO RR and hydroformylation systems in a vial-in-vial reactor, while allowing CO and H transport between catalyst sites. In this manner, 97% aldehyde yield from CO RR and styrene was achieved selectively using a classic homogeneous hydroformylation catalyst in HRh(CO)(PPh ) , and 43% aldehyde yield was obtained using a heterogenized version of this Rh catalyst onto mesoporous silica. This work not only repurposes undesired HER in CO RR and prepares aldehydes from CO without added H , but expands the scope of processes that transform feedstocks all the way to commodity chemicals in a one pass manner.