Stereochemical Control of Chirally Flexible Phosphepines
2007 (English)In: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2007, no 1, 108-115 p.Article in journal (Refereed) Published
The barriers to interconversion of the two enantiomeric atropisomers of 6-methoxy-6,7-dihydro-5H-dibenzo[c,e]phosphepine and that of the diastereomeric forms of 6-(-)menthoxy-6,7-dihydro-3H-dibenzo[c,e]phosphepine were determined by NMR spectroscopical methods to be 19.3 and 18.5 kcalmol(-1), respectively, at 298 K. The ratio of the atropisomers was shown to depend on the group bound to phosphorus. Only complexes with two homochiral ligands bound to the each metal center were obtained upon reaction with [Rh(COD)(2)](+) BF4-. The Rh complexes catalyzed the hydrogenation of alpha-acetamidocinnamate. The major isomer of 6-(-)-menthoxy-6,7-dihydro-5H-dibenzo[c,e]phosphepine was found to exhibit higher activity but to afford a product with lower ee than its diastereomer.
Place, publisher, year, edition, pages
Weinheim: Wiley-VCH Verlag , 2007. Vol. 2007, no 1, 108-115 p.
atropoisomerism, phosphepine, rotational barrier, Rh complex, hydrogenation
IdentifiersURN: urn:nbn:se:kth:diva-12850DOI: 10.1002/ejoc.200600717ISI: 000243303000012ScopusID: 2-s2.0-33846083767OAI: oai:DiVA.org:kth-12850DiVA: diva2:319275