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Photochemical C(sp)-C(sp2) Bond Activation in Phosphaalkynes: A New Route to Reactive Terminal Cyaphido Complexes
Tim Görlich1, Daniel S Frost1, Nico Boback1
1Freie Universität Berlin, Institut für Chemie und Biochemie, Fabeckstr. 34/36, 14195 Berlin, Germany.
Journal of the American Chemical Society
|November 10, 2021
Summary
Photochemical activation of platinum complexes cleaves C-C bonds, forming novel platinum-cyaphido complexes. These complexes react with azides to create triazaphospholato compounds, offering a clean synthesis route.
Area of Science:
- Organometallic Chemistry
- Photochemistry
- Synthetic Chemistry
Background:
- Phosphaalkynes are versatile building blocks in organometallic chemistry.
- Platinum complexes are widely used in catalysis and synthesis.
- Understanding C-C bond activation is crucial for developing new synthetic methodologies.
Purpose of the Study:
- To investigate the photochemical activation of the C(sp)-C(sp2) bond in Pt(0)-aryl-phosphaalkyne complexes.
- To develop a novel synthetic route to terminal Pt(II)-cyaphido complexes.
- To explore the reactivity of these cyaphido complexes in cycloaddition reactions.
Main Methods:
- Photochemical activation of Pt(0)-η2-aryl-phosphaalkyne complexes.
- Characterization of the resulting Pt(II)-cyaphido complexes.
- Investigation of [3+2] cycloaddition reactions with organic azides.
Main Results:
- Selective photochemical activation of the C(sp)-C(sp2) bond was achieved.
- Novel terminal Pt(II)-cyaphido complexes were synthesized via a clean, atom-economic route.
- Pt(II)-cyaphido complexes underwent [3+2] cycloaddition with organic azides to form Pt(II)-triazaphospholato complexes.
- The reverse reductive elimination reaction was observed upon heating.
Conclusions:
- Photochemical C-C bond cleavage in Pt(0)-phosphaalkyne complexes provides an efficient synthesis of Pt(II)-cyaphido complexes.
- These cyaphido complexes are valuable intermediates for constructing heterocycles.
- The developed methodology offers a clean and atom-economic approach to complex organometallic structures.
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