title: Chiral N-hydroxybenzamides as potential catalysts for aerobic asymmetric oxidations.
abstract: Chiral N-hydroxybenzamides (1H-3H) have been synthesized as precursors of chiral short-lived N-oxyl radicals 1(•)-3(•). The latter species have been generated by oxidation of 1H-3H with Pb(OAc)4 or hydrogen abstraction from 1H-3H by the tert-butoxyl radical and characterized by UV-vis spectrophotometry and EPR spectroscopy. Through a kinetic study of the hydrogen atom transfer processes promoted by 1(•)-3(•) from three chiral benzylic substrates (1-phenylethylamine, 1-phenylethanol, and α-vinylbenzyl alcohol), a moderate chiral discrimination has been found, with selectivity factors 0.5 ≤ k(H)(S)/k(H)(R) ≤ 2.
authors.affiliation: Dipartimento di Chimica and Istituto CNR di Metodologie Chimiche (IMC-CNR), Sezione Meccanismi di Reazione, c/o Dipartimento di Chimica, Università di Roma "La Sapienza" , P.le A. Moro, 5 I-00185 Rome, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Capraro
authors.forename: Paola
authors.initials: P
authors.lastname: Franchi
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Lanzalunga
authors.forename: Andrea
authors.initials: A
authors.lastname: Lapi
authors.forename: Marco
authors.initials: M
authors.lastname: Lucarini