title: Synthesis of triazenes with nitrous oxide.
abstract: Triazenes are valuable compounds in organic chemistry and numerous applications have been reported. Furthermore, triazenes have been investigated extensively as potential antitumor drugs. Here, we describe a new method for the synthesis of triazenes. The procedure involves a reagent which is rarely used in synthetic organic chemistry: nitrous oxide (N2 O, "laughing gas"). Nitrous oxide mediates the coupling of lithium amides and organomagnesium compounds while serving as a nitrogen donor. Despite the very inert character of nitrous oxide, the reactions can be performed in solution under mild conditions. A key advantage of the new procedure is the ability to access triazenes with alkynyl and alkenyl substituents. These compounds are difficult to prepare by conventional methods because the required starting materials are unstable. Some of the new alkynyltriazenes were found to display high cytotoxicity in in vitro tests on ovarian and breast cancer cell lines.
authors.affiliation: Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne (Switzerland).
authors.forename: Gregor
authors.initials: G
authors.lastname: Kiefer
authors.forename: Tina
authors.initials: T
authors.lastname: Riedel
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Dyson
authors.forename: Rosario
authors.initials: R
authors.lastname: Scopelliti
authors.forename: Kay
authors.initials: K
authors.lastname: Severin
keywords: Grignard reagents; amides; coupling reactions; nitrous oxide; triazenes