Preparation of Diamidochloro(cyclopentadienyl)titanium Derivatives as Pre‐Catalysts for Olefin Polymerization − X‐ray Molecular Structure of [Ti(η⁵‐C₅H₅){1,2‐C₆H₄(NCH₂CH₂CH₃)₂}Cl] and [Ti{η⁵‐C₅H₄(SiMe₃)}{1,2‐C₆H₄(NCH₂CH₂CH₃)₂}Cl]

Abstract

Keywords: Cyclopentadienyl ligands / N ligands / Olefin polymerization / TitaniumThe synthesis of N,NЈ-alkyl 1,2-phenylenediamines 1,2-C 6 H 4 (NHR) 2 [R = CH 2 CH 2 CH 3 (nPr), CH 2 tBu (Np)] was carried out in three steps by lithiation of the primary 1,2-phenylenediamine, reaction with the appropriate acyl chloride and reduction with LiAlH 4 . The addition of nBuLi to a stirred solution of N,NЈ-alkyl diamines in cold hexane resulted in the immediate deposition of the corresponding lithium salts, which react with [MCp

Studies of the Nature of the Catalytic Species in the α‐Olefin Polymerisation Processes Generated by the Reaction of Diamido(cyclopentadienyl)titanium Complexes with Aluminium Reagents as Cocatalysts

“…[ 28] Preparation of MAO Samples: To obtain MAO with a reduced amount of TMA, a sample of commercial MAO was distilled under vacuum at 20°C. The white powder obtained (polymeric MAO with residual TMA ca.…”

“…[29] Similar results were obtained for the corresponding chloro derivatives which is consistent with the disposition found in the solid state using X-ray crystallography. [28] …”

“…[28] The 1 H resonances (C 6 D 6 , room temperature) of the cyclopentadienyl protons appear at δ ϭ 6.01Ϫ6.15 for the Cp and δ ϭ 1.45Ϫ1.71 for the C 5 Me 5 ligands. The C 5 H 4 (SiMe 3 ) ring protons give AAЈBBЈ spin systems at δ ϭ 6.13Ϫ6.53.…”

Monocyclopentadienyl Phenoxido–Amino and Phenoxido–Amido Titanium Complexes: Synthesis, Characterisation, and Reactivity of Asymmetric Metal Centre Derivatives

“…Examples of these ligands including phenoxido-imino [2][3][4][5][6][7][8][9] are synthesised through well-established synthetic methods from which group 4 metal complexes with tunable electronic and coordination geometry properties have been prepared. In recent years, we have reported the synthesis of a series of cyclopentadienyl titanium complexes containing chelating dialkoxido [10][11][12] and diamido [13,14] ligands and studied the nature of the catalytic species in the α-olefin polymerisation processes generated by the reaction of these complexes with aluminum and boron reagents as cocatalyst. [15] In this paper we report the synthesis and characterisation of secondary phenol-amine compounds RЈNHCH 2 (3,5-R 2 C 6 H 2 -2-OH) obtained from the phenol-imine derivatives RЈN=CH(3,5-R 2 C 6 H 2 -2-OH) and tertiary phenol-amine compounds tBuN(R)CH 2 (3,5-tBu 2 C 6 H 2 -2-OH) derived from the corresponding benzoxazine derivatives.…”

“…[10,11] However, the Ti-N distance remains nearly identical. [13] Finally, the Ti-O-C Ph -C Ph -C methylene -N core appears as a six-membered ring, where the sp 3 methylene carbon atom is placed out of the plane defined by the rest of the atoms. The C-C distances within the cyclopentadienyl ring, Ti-Cg(centroid) distance and Ti-Cl bond length are within the range for monocyclopentadienyl and dicyclopentadienyl titanium complexes.…”