Novel eta(1)-alkynyl zirconium porphyrin complexes: synthesis and characterization of (por)Zr(eta(1)-C CR)(3)Li(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-octa-ethylporphyrinato dianion (oep) or 5,10,15,20-tetraphenylporphyrinato dianion (tpp)] with 3 equiv, of LiC=CR (R = Ph and SiMe3) produces novel alkynyl zirconium(Iv) porphyrin complexes (por)Zr(eta(1)-C=CR)(3)Li(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(eta(1)-CECPh)(3)Li(THF) with anhydrous HCl produces a C-C bond coupled product H2C=CPh(C=CPh) and HC=CPh quantitatively.