Synthesis and reactivity of the monomeric late-transition-metal parent amido complex [Ir(Cp*)(PMe3)(Ph)(NH2)].
The late-transition-metal parent amido compound [Ir(Cp*)(PMe3)(Ph)(NH2)] (2) has been synthesized by deprotonation of the corresponding ammine complex [Ir(Cp*)(PMe3)(Ph)(NH3)][OTf] (6) with KN(SiMe3)2. An X-ray structure determination has ascertained its monomeric nature. Proton-transfer studies indicate that 2 can successfully deprotonate p-nitrophenylacetonitrile, aniline, and phenol. Crystallographic analysis has revealed that the ion pair [Ir(Cp*)(PMe3)(Ph)(NH3)][OPh] (8) exists as a hydrogen-bonded dimer in the solid state. Reactions of 2 with isocyanates and carbodiimides lead to overall insertion of the heterocumulenes into the N--H bond of the Ir-bonded amido group, demonstrating the ability of 2 to act as an efficient nucleophile. Intriguing reactivity is observed when amide 2 reacts with CO or 2,6-dimethylphenyl isocyanide. eta4-Tetramethylfulvene complexes [Ir(eta4-C5Me4CH2)(PMe3)(Ph)(L)] (L=CO (15), CNC6H3-2,6-(CH3)2 (16)) are formed in solution through displacement of the amido group by the incoming ligand followed by deprotonation of a methyl group on the Cp* ring and liberation of ammonia. Conclusive evidence for the presence of the Ir-bonded eta4-tetramethylfulvene moiety in the solid state has been provided by an X-ray diffraction study of complex 16.
Institut für Anorganische Chemie, Universität Würzburg, Germany.
Daniela
D
Rais
Robert G
RG
Bergman
D000577:Amides / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D003517:Cyclopentanes / Q000737:chemistry; D007495:Iridium / Q000737:chemistry*; D008024:Ligands; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D010720:Phosphines / Q000737:chemistry
D000577:Amides; D003517:Cyclopentanes; D008024:Ligands; D009942:Organometallic Compounds; D010720:Phosphines; D007495:Iridium