Synthesis of neutral mixed sandwich CH2-SiR2 bridged [2]cobaltoarenophanes from the dilithiation of Cb*CoCp [Co(η4-C4Me4)(η5-C5H5)]

The dilithiation of [Co(eta(4)-C4Me4)(eta(5)-C5H5)] to give [Co(eta(4)-C4Xe3CH2Li)(eta(5)-C5H4Li)]center dot PMDETA and the subsequent synthesis and characterization of the CH2-SiR2-bridged [2]-cobaltoarenophanes is reported. This is the first development in the chemistry of neutral 18-electron metalloarenophanes featuring a group 9 transition metal.