On the origin of cis selectivity in the cyclization of N-protected 2-substituted 3-aza-5-hexenyl radicals: a density functional study
2004 (English)In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 69, no 5, 1487-1491 p.Article in journal (Refereed) Published
Cyclization of the N-dimethylphosphinoyl-2-methyl-3-aza-5-hexenyl radical has been studied at the UB3LYP/6-31+G(d)//UB3LYP/6-31G(d) hybrid density functional level. The corresponding radical precursor has been synthesized and found to give cis/trans ratios of up to 10/1 in reductive radical cyclizations. The relative energies of reactant and transition state conformers were determined. In discord with the Beckwith-Houk model, it has been found that chair-axial transition states, which lead to cis products, are lowest in energy, rationalizing the observed experimental diastereoselectivity.
Place, publisher, year, edition, pages
2004. Vol. 69, no 5, 1487-1491 p.
IdentifiersURN: urn:nbn:se:uu:diva-90422DOI: 10.1021/jo030294hPubMedID: 14987001OAI: oai:DiVA.org:uu-90422DiVA: diva2:162771