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A silicon–carbonyl complex stable at room temperature


Main-group-element compounds with energetically high-lying donor and low-lying acceptor orbitals are able to mimic chemical bonding motifs and reactivity patterns known in transition metal chemistry, including small-molecule activation and catalytic reactions. Monovalent group 13 compounds and divalent group 14 compounds, particularly silylenes, have been shown to be excellent candidates for this purpose. However, one of the most common reactions of transition metal complexes, the direct reaction with carbon monoxide and formation of room-temperature isolable carbonyl complexes, is virtually unknown in main-group-element chemistry. Here, we show the synthesis, single-crystal X-ray structure, and density functional theory computations of a room-temperature-stable silylene carbonyl complex [L(Br)Ga]2Si:–CO (L = HC[C(Me)N(2,6-iPr2-C6H3)]2), which was obtained by direct carbonylation of the electron-rich silylene intermediate [L(Br)Ga]2Si:. Furthermore, [L(Br)Ga]2Si:–CO reacts with H2 and PBr3 with bond activation, whereas the reaction with cyclohexyl isocyanide proceeds with CO substitution.

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Fig. 1: A selection of Si and Ge compounds formed in reactions of silylenes and germylene with CO.
Fig. 2: Synthesis of compounds 1–6 and exemplary reactions of 5.
Fig. 3: Molecular structures of compounds 3–6 as derived from single-crystal X-ray crystallography.
Fig. 4: Thermochemical comparisons.

Data availability

All data generated or analysed during this study are included in this Article (and its Supplementary Information). The structures of 16 in the solid state were determined by single-crystal X-ray diffraction and the crystallographic data have been deposited with the Cambridge Crystallographic Data Centre under nos. CCDC 1943186 (1), 1943187 (2), 1943188 (3), 1943189 (4), 1943190 (5) and 1967024 (6). Copies of the data can be obtained free of charge on application to CCDC.


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This work was supported by the University of Duisburg–Essen and the Alexander-von-Humboldt Foundation (a scholarship to L.S.). We thank the Deutsche Forschungsgemeinschaft for partial support within the Priority Program SPP 1807 (control of London dispersion interactions in molecular chemistry) and T. Benter and H. Kersten for mass spectroscopy measurements.

Author information




C.G., S.S. and P.R.S. conceived the experiments. S.S. and P.R.S. supervised the study. C.G. and J.S. performed the synthetic studies, C.W. the single-crystal X-ray diffraction studies, and L.S. the computational experiments. C.G., S.S. and P.R.S. wrote the manuscript, with input from all authors. All authors analysed the results and commented on the manuscript.

Corresponding authors

Correspondence to Peter R. Schreiner or Stephan Schulz.

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The authors declare no competing interests.

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Supplementary information

Supplementary Information

Experimental details including methods, synthetic procedures, characterization data (NMR, IR, UV–vis spectra), crystallographic details and computational details.

Crystallographic data

CIF for compound 1; CCDC reference 1943186

Crystallographic data

CIF for compound 2; CCDC reference 1943187

Crystallographic data

CIF for compound 3; CCDC reference 1943188

Crystallographic data

CIF for compound 4; CCDC reference 1943189

Crystallographic data

CIF for compound 5; CCDC reference 1943190

Crystallographic data

CIF for compound 6; CCDC reference 1967024

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Ganesamoorthy, C., Schoening, J., Wölper, C. et al. A silicon–carbonyl complex stable at room temperature. Nat. Chem. 12, 608–614 (2020).

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