AI Article Synopsis
- The study presents a new asymmetric photodimerization reaction using coumarin derivatives with a specific auxiliary, resulting in mainly head-to-tail dimers.
- The reaction showed a moderate level of diastereoselectivity, achieving a ratio of 75 : 25 for the products.
- The proposed mechanism for this selectivity involves density functional theory (DFT) calculations, suggesting that the benzyl group of the auxiliary, paired with a Lewis acid, influences the reaction site's shielding and selectivity.
Article Abstract
A novel asymmetric photodimerization reaction of coumarin derivatives bearing the ()-4-benzyl-2-oxazolidinone auxiliary provides only the -head-to-tail (-HT) dimer with moderate diastereoselectivity (up to 75 : 25). The mechanism of complete -HT selectivity and moderate diastereoselectivity is proposed based on the result of density functional theory (DFT) calculation. The benzyl group of the ()-4-benzyl-2-oxazolidinone auxiliary in combination with a Lewis acid exerts effective diastereofacial shielding of the reaction site.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9063662 | PMC |
| http://dx.doi.org/10.1039/c9ra00822e | DOI Listing |
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