The open d-shell enforces the active space in 3d metal catalysis: highly enantioselective chromium(II) pincer catalysed hydrosilylation of ketones
Bis(oxazolinyldimethylmethyl)pyrrol (PdmBox) stereodirecting ligands provided the key to the chromium(II)-catalysed highly enantioselective hydrosilylation of ketones. A rare square planar, chiral chromium(II) alkyl complex was found to serve as a potent precatalyst for the reduction of a broad rang...
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| Main Authors: | , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
2018
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| In: |
Chemical communications
Year: 2018, Volume: 54, Issue: 66, Pages: 9139-9142 |
| ISSN: | 1364-548X |
| DOI: | 10.1039/C8CC05172K |
| Online Access: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1039/C8CC05172K Verlag, lizenzpflichtig, Volltext: https://pubs.rsc.org/en/content/articlelanding/2018/cc/c8cc05172k 
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| Author Notes: | Christian H. Schiwek, Vladislav Vasilenko, Hubert Wadepohl and Lutz H. Gade |
| Summary: | Bis(oxazolinyldimethylmethyl)pyrrol (PdmBox) stereodirecting ligands provided the key to the chromium(II)-catalysed highly enantioselective hydrosilylation of ketones. A rare square planar, chiral chromium(II) alkyl complex was found to serve as a potent precatalyst for the reduction of a broad range of aryl alkyl and dialkyl ketone derivatives. The stereoelectronic preference of the open d4 shell of chromium(II) firmly locks the molecular catalyst in a square planar geometry giving rise to two blocked quadrants of the coordination sphere. This earth-abundant base metal catalytic platform produces the corresponding chiral alcohols in excellent isolated yields with up to 98 %ee under mild reaction conditions (−40 °C to rt) and at low catalyst loadings (as low as 0.5 mol%). |
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| Item Description: | Gesehen am 18.03.2020 |
| Physical Description: | Online Resource |
| ISSN: | 1364-548X |
| DOI: | 10.1039/C8CC05172K |