π-Olefin-Iridium-Komplexe, IX [1] Bis(η4-butadien)-σ-organyl-iridium-Verbindungen / π-Olefin Iridium Complexes, IX [1] Bis(η4-butadiene)-cr-organyl-iridium Compounds

Abstract

Complexes of the type [L2IrR] (L = butadiene, isoprene, piperylene, 1,4- and 2,3- dimethylbutadiene; R = CH3, C6H5) have been synthesized by reactions of [L2IrCl] with LiR in hexane. With L = 2,3-dimethylbutadiene, [L2IrR] compounds with higher alkyl groups R (e.g. η-C3H7, η-C4H9) can be obtained which for steric reasons are inert against β-elimination. The system [L2IrCl]/L/LiAlH4 (L = 2,3-dimethylbutadiene) yields [L2IrR] with R = 2,3-dimethylbutene-2-yl. The complexes were characterized by NMR and mass spectra