First isocyanoazulene and its homoleptic complexes.
An efficient synthesis of remarkably stable 6-isocyanoazulene (CN6Az), the first nonbenzenoid organic isocyanide, is described. Its superb pi-accepting potential as a ligand was demonstrated through cyclic voltammetry studies on the binary complexes [Cr(CN6Az)6]0/+. The paramagnetic shift patterns for [Cr(CN6Az)6]+, the only azulenic pi-system studied by paramagnetic NMR, suggest that Cr(dpi) --> CN6Az(ppi*) electron delocalization involves both rings of the azulenyl substituents in [Cr(CN6Az)6]+. This conclusion is supported by density functional theory calculations on the complex [Cr(CN6Az)6][BF4].
Robinson
Randall E
RE
Department of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, KS 66045, USA.
Holovics
Thomas C
TC
Deplazes
Stephan F
SF
Lushington
Gerald H
GH
Powell
Douglas R
DR
Barybin
Mikhail V
MV
D052176:Azulenes; D018360:Crystallography, X-Ray; D003508:Cycloheptanes / Q000138:chemical synthesis / Q000737:chemistry*; D017953:Isocyanates / Q000138:chemical synthesis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure
D052176:Azulenes; D003508:Cycloheptanes; D017953:Isocyanates; C005525:azulene