title: Intramolecular cycloadditions of photogenerated azaxylylenes with oxadiazoles provide direct access to versatile polyheterocyclic ketopiperazines containing a spiro-oxirane moiety.
abstract: Photogenerated azaxylylenes undergo intramolecular cycloadditions to 1,3,4-oxadiazole pendants, which are accompanied by concomitant release of dinitrogen, yielding functionalized ketopiperazinoquinolinols containing an oxirane moiety fused to the quinolinole moiety while spiro-connected to diketopiperazine. These primary photoproducts are reactive versatile intermediates which can be further derivatized under nucleophilic SN1- or SN2-like ring opening of the oxirane moiety. The oxidized quinolinones undergo new rearrangements under the conditions of the Schmidt reaction, leading to unprecedented triazacanoindolinones.
authors.affiliation: Department of Chemistry and Biochemistry, University of Denver , Denver, Colorado 80208, United States.
authors.forename: N N Bhuvan
authors.initials: NN
authors.lastname: Kumar
authors.forename: Dmitry M
authors.initials: DM
authors.lastname: Kuznetsov
authors.forename: Andrei G
authors.initials: AG
authors.lastname: Kutateladze