916249-80-4Relevant articles and documents
Intrazeolite photooxygenation of chiral alkenes. Control of facial selectivity by confinement and cation-π interactions
Stratakis, Manolis,Raptis, Christos,Sofikiti, Nikoletta,Tsangarakis, Constantinos,Kosmas, Giannis,Zaravinos, Ioannis-Panagiotis,Kalaitzakis, Dimitris,Stavroulakis, Dimitris,Baskakis, Constantinos,Stathoulopoulou, Aggeliki
, p. 10623 - 10632 (2007/10/03)
Depending on the nature of the substituents on the stereogenic carbon atom, the ene reaction of singlet oxygen with several chiral alkenes by confinement within thionin-supported zeolite NaY, may exhibit significant changes on facial selectivity by comparison to their photooxygenation reaction in solution. It is proposed that, apart from the conformational consequences as a result of the alkene confinement within the zeolite cavities, a synergism between Na+-π interactions and singlet oxygen-Na+ interactions plays a significant role in the transition states of ene hydroperoxidation. Within NaY, the diastereoselectivity may significantly depend on the site selectivity, as probed through specific deuterium labelling of trisubstituted alkenes bearing a gem-dimethyl group. In certain cases, a remote stereogenic centre relative to the reacting double bond may induce enhanced diastereoselection and regioselectivity.
