Synthesis of unsymmetrical N-carboranyl NHCs: directing effect of the carborane anion.
The syntheses of unsymmetrical N-heterocyclic carbenes (NHCs) that contain a single N-bound icosahedral carborane anion substituent are reported. Both anionic C-2 and doubly deprotonated dianionic C-2/C-5 NHC lithium complexes are isolated. The latter species is formed selectively, which reveals a surprising directing effect conveyed by icosahedral carborane anion substituents.
Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, D.F. 04360, Mexico.
Matthew J
MJ
Asay
Steven P
SP
Fisher
Sarah E
SE
Lee
Fook S
FS
Tham
Dan
D
Borchardt
Vincent
V
Lavallo