Abstract
The reaction of 1 equiv of the deprotonated (sterically demanding) aminopyridine Ap*-H (Ap*-H = (2,6-diisopropylphenyl)-[6-(2,4,6-triisopropylphenyl)pyridin-2-yl]amine) with [CrCl3(thf)(3)] led selectively to the monomeric complex [Ap*CrCl2(thf)(2)]. Methylation of [Ap*CrCl2(thf)(2)] by methyllithium gave rise to a mixture of a dichromium methylidene and a dichromium methyl complex. Alkylation of [Ap'CrCl2(thf)(2)] (Ap'-H = (2,6-diisopropylphenyl)-[6-(2,6-dimethylphenyl)pyridin-2-yl]amine) afforded selectively the dimethyl complex [Ap'2CrCr(CH3)(2)]. In addition to reductive alkylation, oxidative addition can be used to synthesize chromium methyl complexes. Selective oxidative addition was observed when CH3I was reacted with the quintuply bonded Cr-I dimer [Ap'CrCrAp']. Here, the Grignard-like Cr-2 compound [Ap'2CrCr(mu-I)(mu-CH3)] was formed. DFT calculations were performed to investigate the electronic structure of the organometallic complexes.