Novel η¹-alkynyl zirconium porphyrin complexes: synthesis and characterization of (por)Zr(η¹-C[triple bond, length half m-dash]CR)₃Li(THF) [por = octaethylporphyrinato (oep) or tetraphenylporphyrinato dianion (tpp); R = Ph, SiMe₃]

Abstract

Reaction of (por)ZrCl₂ [por = 2,3,7,8,12,13,17,18-octaethylporphyrinato dianion (oep) or 5,10,15,20-tetraphenylporphyrinato dianion (tpp)] with 3 equiv. of LiC[triple bond, length half m-dash]CR (R = Ph and SiMe₃) produces novel alkynyl zirconium(IV) porphyrin complexes (por)Zr(η¹-C[triple bond, length half m-dash]CR)₃Li(THF) in which three alkynyl ligands are coordinated to the zirconium center in a piano stool fashion and the Li⁺ ion is bound to the pocket formed by three alkynyl ligands; treatment of (por)Zr(η¹-C[triple bond, length half m-dash]CPh)₃Li(THF) with anhydrous HCl produces a C–C bond coupled product H₂C[double bond, length half m-dash]CPh(C[triple bond, length half m-dash]CPh) and HC[triple bond, length half m-dash]CPh quantitatively.

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