Mikhail V. Nikulin

Titanium and zirconium complexes with η5: η1-4-(alkyl/arylamino)(dimethyl)silylindene ligands as catalysts for ethene polymerization

First members of a novel family of constrained geometry complexes of titanium and zirconium containing a short bridge between the amide and inden-4-yl fragments were obtained. When activated with methylaluminoxane, these complexes can be used as highly active catalysts for ethene polymerization producing high-molecular-weight polymers.

The cocrystal 10-(2-methyl-4-phenyl-1H-inden-6-yl)-10H-phenothia­zine–10-(2-methyl-7-phenyl-1H-inden-5-yl)-10H-phenothia­zine (0.54/0.46)

The title compound, 0.535C28H21NS.0.465C28H21NS, was synthesized by palladium-catalysed amination. The structure is composed of two isomeric molecules, viz. 10-(2-methyl-4-phenyl-1H-inden-6-yl)-10H-phenothiazine, and 10-(2-methyl-7-phenyl-1H-inden-5-yl)-10H-phenothiazine, in the refined ratio 0.535 (12):0.465 (12). The isomers differ by the localization of the double bond in the cyclopentadiene ring. There are two sites in the structure that are occupied by the isomers. The respective isomers are occupationally disordered in each site, the refined proportions being 0.640 (6):0.360 (6) and 0.43 (1):0.57 (1). Moreover, each isomeric molecule is chiral; due to the crystallographic centres of symmetry, the molecules are also present in enantiomeric pairs. The crystal structure is stabilized by weak π–π [C⋯C = 3.389 (2) Å] interactions.