Migratory Insertion Reactions in Asymmetrical Guanidinate-Supported Zirconium Complexes
收藏资源简介：
The new diguanidinate-supported dibenzylzirconium complexes [Zr{κ2N,N′-(N-i-Pr)(NAr)CNH(i-Pr)}2(CH2Ph)2] (Ar = 4-t-BuC6H4 (1), 4-BrC6H4 (2)) and [Zr{κ2N,N′-(NEt)(N-t-Bu)CNMe2}2(CH2Ph)2] (3) have been prepared. Complexes 1 and 2 were synthesized by protonolysis of [Zr(CH2Ph)4] with the guanidine derivatives and complex 3 by treating [Zr{κ2N,N′-(NEt)(N-t-Bu)CNMe2}2Cl2] (4) with MgCl(CH2Ph). The treatment of 1–3 with 2,6-dimethylphenyl isocyanide (XyNC) results in migratory insertion and formation of the terminal imido species [Zr{κ2N,N′-(N-i-Pr)(N(Ar))CNH(i-Pr)}2{N(2,6-Me2C6H3)}] (Ar = 4-t-BuC6H4 (7), 4-BrC6H4 (8)) with 1 and 2, respectively, whereas the analogous reaction with 3 leads to the enediamido complex [Zr{κ2N,N′-(NEt)(N-tBu)CNMe2)}2{N(2,6-Me2C6H3)(CH2Ph)CC(CH2Ph)N(2,6-Me2C6H3)}] (9). All the intermediate iminoacyl complexes have been characterized, and the molecular structures of 2, 4, and 9 have been determined by single-crystal X-ray diffraction.
