Details

Autor(en) / Beteiligte

• Xiong, Yun
• Yao, Shenglai
• Müller, Robert
• Kaupp, Martin
• Driess, Matthias

Titel

From silicon(II)-based dioxygen activation to adducts of elusive dioxasiliranes and sila-ureas stable at room temperature

Ist Teil von

• Nature chemistry, 2010-07, Vol.2 (7), p.577

Ort / Verlag

England

Erscheinungsjahr

2010

Quelle

MEDLINE

Beschreibungen/Notizen

• Dioxygen activation for the subsequent oxygenation of organic substrates that involves cheap and environmentally friendly chemical elements is at the cutting edge of chemical research. As silicon is a non-toxic and highly oxophilic element, the use of silylenes could be attractive for facile dioxygen activation to give dioxasiliranes with a SiO(2)-peroxo ring as versatile oxo-transfer reagents. However, the latter are elusive species, and have been generated and studied only in argon matrices at -233 degrees C. Recently, it was demonstrated that unstable silicon species can be isolated by applying the concept of donor-acceptor stabilization. We now report the first synthesis and crystallographic characterization of dioxasiliranes stabilized by N-heterocyclic carbenes that feature a three-membered SiO(2)-peroxide ring, isolable at room temperature. Unexpectedly, these can undergo internal oxygen transfer in toluene solution at ambient temperature to give a unique complex of cyclic sila-urea with C=O --> Si=O interaction and the shortest Si=O double-bond distance reported to date.