Synthesis and characterization of chromium(I) bis(η6-toluene) derivatives containing sterically demanding anions

In the solid state, a cis-eclipsed conformation of the toluene rings is found for [Cr(η6-CH3C6H5)2][dbcp] · THF, [dbcp]− = 1,2-dibenzoylcyclopentadienyl, whereas two different conformations (an almost cis-eclipsed and a quasi-staggered one) are observed in the unit cell of [Cr(η6-CH3C6H5)2][pcmcp], [pcmcp]− = pentakis(methoxycarbonyl)cyclopentadienyl. In [Cr(η6-CH3C6H5)2][dbcp] · THF, six cations and six anions form the walls of a channel parallel to the crystallographic axis c, which contains six molecules of THF per repeating unit along c.