Details

Autor(en) / Beteiligte

• Frye, Connor W
• Egger, Dominic T
• Kounalis, Errikos
• Pearce, Adam J
• Cheng, Yukun
• Tonks, Ian A

Titel

α-Diimine synthesis via titanium-mediated multicomponent diimination of alkynes with C-nitrosos

Ist Teil von

• Chemical science (Cambridge), 2022-02, Vol.13 (5), p.1469-1477

Ort / Verlag

England: Royal Society of Chemistry

Erscheinungsjahr

2022

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• α-Diimines are commonly used as supporting ligands for a variety of transition metal-catalyzed processes, most notably in α-olefin polymerization. They are also precursors to valuable synthetic targets, such as chiral 1,2-diamines. Their synthesis is usually performed through acid-catalyzed condensation of amines with α-diketones. Despite the simplicity of this approach, accessing unsymmetrical α-diimines is challenging. Herein, we report the Ti-mediated intermolecular diimination of alkynes to afford a variety of symmetrical and unsymmetrical α-diimines through the reaction of diazatitanacyclohexadiene intermediates with C-nitrosos. These diazatitanacycles can be readily accessed the multicomponent coupling of Ti[triple bond, length as m-dash]NR imidos with alkynes and nitriles. The formation of α-diimines is achieved through formal [4 + 2]-cycloaddition of the C-nitroso to the Ti and γ-carbon of the diazatitanacyclohexadiene followed by two subsequent cycloreversion steps to eliminate nitrile and afford the α-diimine and a Ti oxo.