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Updated: Jan 17, 2026
07:36
Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
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Iminophosphonamido stannylenes enable quantitative CO2 conversion to isocyanates
Shintaro Takahashi1, Akihiko Ishii1, Norio Nakata1
1Department of Chemistry, Graduate School of Science and Engineering, Saitama University, Shimo-okubo, Sakura-ku, Saitama 338-8570, Japan. nakata@chem.saitama-u.ac.jp.
Chemical Communications (Cambridge, England)
|September 15, 2025
Summary
Iminophosphonamido-supported silylaminostannylenes activate carbon dioxide (CO2) to form isocyanates. This CO2 valorisation pathway involves carbamatostannylene intermediates and silyl migration, offering a novel route for chemical synthesis.
Area of Science:
- Organometallic Chemistry
- Main-Group Chemistry
- Catalysis
Background:
- Carbon dioxide (CO2) utilization is crucial for sustainable chemistry.
- Main-group element compounds offer unique reactivity for CO2 activation.
- Isocyanate synthesis is vital for polymer and pharmaceutical industries.
Purpose of the Study:
- To investigate the CO2 activation capability of iminophosphonamido-supported silylaminostannylenes.
- To elucidate the reaction mechanism and intermediates involved in CO2 valorisation.
- To explore a novel pathway for isocyanate formation from CO2.
Main Methods:
- Synthesis of iminophosphonamido-supported silylaminostannylenes.
- Reaction of the silylaminostannylenes with carbon dioxide.
- Characterization of reaction products.
- Density Functional Theory (DFT) calculations to model the reaction mechanism.
Main Results:
- Iminophosphonamido-supported silylaminostannylenes successfully activate CO2.
- The reaction proceeds via carbamatostannylene intermediates.
- Siloxystannylene and isocyanates are formed as products.
- DFT calculations confirm a two-step rearrangement mechanism involving nucleophilic attack and silyl migration.
Conclusions:
- This study presents a novel CO2 valorisation strategy using main-group chemistry.
- The developed method provides a rare example of direct isocyanate formation from CO2.
- The findings offer new insights into the reactivity of silylaminostannylenes and their potential in catalysis.
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