Synthesis of a Naphthalene-Bridged Bis(guanidinato)ytterbium(II) Complex and an Unexpected Pathway in Its Reaction with CH₃CN, p‑ClC₆H₄CH₂CN, and Ph₂CHCN

A novel binuclear ytterbium­(II) complex supported by a naphthalene-bridged bis­(guanidinate) ligand, [Yb­(μ-L)­(THF)]₂ (1; L = 1,8-C₁₀H₆{NC­(NⁱPr)­(NHⁱPr)}₂), was synthesized by the reduction reaction of [Yb­(L)­Cl­(THF)₂] with Na/K alloy in THF and structurally characterized. The reactions of 1 with CH₃CN and p-ClC₆H₄CH₂CN resulted in the formation of the corresponding binuclear (crotononitrileamido)­ytterbium­(III) complexes [Yb­(L)­(μ­(N,N′)-N­(H)­C­(Me)C­(H)­CN)­(THF)]₂ (2) and [Yb­(L)­(μ­(N,N′)-N­(H)­C­(CH₂C₆H₄-p-Cl)C­(C₆H₄-p-Cl)­CN)­(THF)]₂ (3) via metalation of the nitrile, followed by insertion of a second nitrile molecule. Treatment of 1 with the bulkier Ph₂CHCN afforded the mononuclear (keteniminato)­ytterbium­(III) complex [Yb­(L)­(NCCPh₂)­(THF)₂] (4) by deprotonation of Ph₂CHCN. The molecular structures of 2–4 have been determined.