Catalytic transfer hydrogenation of N<sub>2</sub> to NH<sub>3</sub> via a photoredox catalysis strategy.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 36288295.
- Also identified by DOI 10.1126/sciadv.ade3510 and PMC identifier 9604530.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Inspired by momentum in applications of reductive photoredox catalysis to organic synthesis, photodriven transfer hydrogenations toward deep (>2 e<sup>-</sup>) reductions of small molecules are attractive compared to using harsh chemical reagents. Noteworthy in this context is the nitrogen reduction reaction (N<sub>2</sub>RR), where a synthetic photocatalyst system had yet to be developed. Noting that a reduced Hantzsch ester (HEH<sub>2</sub>) and related organic structures can behave as 2 e<sup>-</sup>/2 H<sup>+</sup> photoreductants, we show here that, when partnered with a suitable catalyst (Mo) under blue light irradiation, HEH<sub>2</sub> facilitates delivery of successive H<sub>2</sub> equivalents for the 6 e<sup>-</sup>/6 H<sup>+</sup> catalytic reduction of N<sub>2</sub> to NH<sub>3</sub>; this catalysis is enhanced by addition of a photoredox catalyst (Ir). Reductions of additional substrates (nitrate and acetylene) are also described.