heterogeneous ziegler-natta and homogeneous metallocene catalysts exhibit greatly different active sitenature in olefin polymerization. in our previous study, it was reported that mgcl2-supported titanocenecatalysts can generate both ziegler-natta-type and metallocene-type active sites according to the type of activators.the dual active site nature of the supported titanocene catalysts was furt...

The title compound, C(11)H(16)Cl(4), was synthesized by the reaction of (1S)-β-pinene with triethyl-amine in the presence of ZnCl(2). The cyclo-hexene ring assumes a half-boat conformation. The crystal packing is governed only by van der Waals inter-actions. The structure, which has been refined in P2(1), presents a striking P2(1)/m pseudosymmetry.

The title compound, C21H42O5Si2, was synthesized from (3R,4S,5R)-methyl 3,5-bis-[(tert-butyl-dimethyl-sil-yl)-oxy]-4-hy-droxy-cyclo-hex-1-ene-carboxyl-ate by an esterification reaction. The cyclo-hexene ring adopts a half-chair conformation. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming helical chains propagating along [010].

The reactions of Ar'GaGaAr' (Ar' = C(6)H(3)-2,6-(C(6)H(3)-2,6-(i)Pr(2))(2)) with alkenes revealed the addition of two olefins per Ar'GaGaAr' under ambient conditions for ethylene, propene, 1-hexene and styrene but no reactions with more hindered or cyclic olefins.

In the title compound, C(18)H(18)N(2)O, the cyclo-hexene and cyclo-hexane rings of the bicyclo-[2.2.2]oct-5-ene unit adopt distorted boat conformations. In the crystal, mol-ecules exist as C-H⋯N hydrogen-bonded centrosymmetric R(2) (2)(14) dimers, which are further linked by C-H⋯π inter-actions.

The carbazole unit of the title mol-ecule, C(12)H(10)ClNO, is not planar. The dihedral angle between the benzene and pyrrole rings is 1.35 (10)°. The cyclo-hexene ring adopts an envelope conformation. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds form centrosymmetric dimers.

The title compound, C26H42ClNO2, is a 3β-chloro steroid with a Weinreb amide at the C-24 position. The two cyclo-hexane and the cyclo-hexene rings adopt chair and boat conformations, respectively. The cyclo-pentane ring has an envelope conformation.

In the title compound, C(21)H(30)O(3), the five-membered ring adopts an envelope conformation, the cyclo-hexene ring displays a half-chair conformation and the two cyclo-hexane rings have normal chair conformations. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonding links the mol-ecules into supra-molecular chains running along [100].

The title compound, C(21)H(26)O, was semisynthesized from isocostic acid, isolated from the aerial part of Inula Viscosa- (L) Aiton [or Dittrichia Viscosa- (L) Greuter]. The cyclo-hexene ring has a half-chair conformation, whereas the cyclo-hexane ring displays a chair conformation.