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Carbon dioxide hydrogenation catalysed by well-defined Mn(i) PNP pincer hydride complexes.

ABSTRACT: The catalytic reduction of carbon dioxide is of great interest for its potential as a hydrogen storage method and to use carbon dioxide as C-1 feedstock. In an effort to replace expensive noble metal-based catalysts with efficient and cheap earth-abundant counterparts, we report the first example of Mn(i)-catalysed hydrogenation of CO₂ to HCOOH. The hydride Mn(i) catalyst [Mn(PNP^NH-iPr)(H)(CO)₂] showed higher stability and activity than its Fe(ii) analogue. TONs up to 10?000 and quantitative yields were obtained after 24 h using DBU as the base at 80 °C and 80 bar total pressure. At catalyst loadings as low as 0.002 mol%, TONs greater than 30?000 could be achieved in the presence of LiOTf as the co-catalyst, which are among the highest activities reported for base-metal catalysed CO₂ hydrogenations to date.

SUBMITTER: Bertini F

PROVIDER: S-EPMC5613213 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Carbon dioxide hydrogenation catalysed by well-defined Mn(i) PNP pincer hydride complexes.

Bertini Federica F Glatz Mathias M Gorgas Nikolaus N Stöger Berthold B Peruzzini Maurizio M Veiros Luis F LF Kirchner Karl K Gonsalvi Luca L

Chemical science 20170504 7

The catalytic reduction of carbon dioxide is of great interest for its potential as a hydrogen storage method and to use carbon dioxide as C-1 feedstock. In an effort to replace expensive noble metal-based catalysts with efficient and cheap earth-abundant counterparts, we report the first example of Mn(i)-catalysed hydrogenation of CO2 to HCOOH. The hydride Mn(i) catalyst [Mn(PNPNH-iPr)(H)(CO)2] showed higher stability and activity than its Fe(ii) analogue ...[more]

PMID: 28970889

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