AI Article Synopsis
- The study explores a titanium(III)-catalyzed method for synthesizing α-hydroxyketones from ketones and nitriles, demonstrating an efficient and stereoselective process.
- A series of advanced techniques, including EPR, ESI-MS, and DFT calculations, were used to uncover the mechanism, highlighting that the formation of C-C bonds is the rate-limiting step controlled by radical combinations of titanium(III) species.
- The research identifies a key cationic titanocene-nitrile complex and explains how the addition of Et3N·HCl enhances yield and enantioselectivity by facilitating the radical coupling process.
Article Abstract
The titanium(III)-catalyzed cross-coupling between ketones and nitriles provides an efficient stereoselective synthesis of α-hydroxyketones. A detailed mechanistic investigation of this reaction is presented, which involves a combination of several methods such as EPR, ESI-MS, X-ray, in situ IR kinetics, and DFT calculations. Our findings reveal that C-C bond formation is turnover-limiting and occurs by a catalyst-controlled radical combination involving two titanium(III) species. The resting state is identified as a cationic titanocene-nitrile complex and the beneficial effect of added Et3N·HCl on yield and enantioselectivity is elucidated: chloride coordination initiates the radical coupling. The results are fundamental for the understanding of titanium(III)-catalysis and of relevance for other metal-catalyzed radical reactions. Our conclusions might apply to a number of reductive coupling reactions for which conventional mechanisms were proposed before.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/jacs.5b09223 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!