Steric Manipulation of the Reductive Reactivity of Ytterbocenes toward 2-(((2,6-Diisopropylphenyl)imino)methyl)pyridine: Insertion of the NC Bond into the Yb−Indenyl Bond or Oxidative Cleavage of the η⁵ Yb−Cp (Cp = C₁₃H₉, Cp*) Bond

Unprecedented NC bond insertion into the η5 Yb−C9H7 bond occurs in the reaction of 2-(((2,6-diisopropylphenyl)imino)methyl)pyridine with (C9H7)2Yb(THF)2 and affords the Yb(III) derivative [Yb(η5-C9H7){N(2,6-i-Pr2C6H3)CH(C9H7)(C5H4N)}{2,6-i-Pr2C6H3NCH(C5H4N)•-}]. For the complexes Cp2Yb(THF)2 (Cp = C13H9, Cp*) coordinated by bulkier η5 ligands the same reaction results in an oxidative cleavage of the η5 Yb−Cp (Cp = C13H9, Cp*) bond and formation of [Yb{(2,6-i-Pr2C6H5NCH(C5H4N)•-}3] and [Yb(C5Me5){(2,6-i-Pr2C6H3NCH(C5H4N)•-}2], respectively.