A range of Zr(IV) and Hf(IV) complexes of arene-substituted cyclopentadienyl ligands have been prepared and tested in ethylene oligomerisation. The complexes prepared were designed to be precatalysts to active species which have been predicted, through theoretical studies, to lead to selective ethylene trimerisation. While there is evidence for selective 1-hexene formation in the liquid fractio...

The title compound, C(12)H(12)Cl(2)O(2), has a bicyclic skeleton containing cyclo-hexene and benzene fragments. The cyclo-hexene ring adopts a half-chair conformation with displacements of two atoms out of the least-squares plane of 0.311 (2) and -0.336 (2) Å. The Cl atoms are trans-positioned.

In the title compound, C(17)H(17)BrN(2)O, the N-containing ring adopts an envelope conformation with the C atom carrying the phenyl ring displaced by -0.531 (9) Å from the plane defined by the remaining five atoms (r.m.s. deviation = 0.0099 Å). The benzene ring is almost orthogonal to the ring to which it is attached, the C(CN)-C-C(Ph)-C(Ph) torsion angle being -101.3 (7)°. The cyclo-hexene rin...

In the title compound, C(18)H(17)ClN(2)O(2)·C(3)H(6)O, the 4H-pyran ring is nearly planar [maximum deviation = -0.108 (1) Å] and the cyclo-hexene ring is puckered [puckering parameters Q(T) = 0.4596 (17) Å, θ = 55.9 (2)° and ϕ = 226.5 (3)°]. The 4H-pyran ring is approximately perpendicular to the benzene ring [dihedral angle = 84.35 (7)°] and is almost coplanar with the mean plane of the cyclo-...

In the title compound, C(20)H(22)O(5), an S(6) ring motif is formed by an intra-molecular C-H⋯O hydrogen bond, which contributes to the stabilization of the mol-ecule. In the xanthene system, the cyclo-hexane ring adopts a chair conformation, the cyclo-hexene ring adopts a half-boat conformation and the tetra-hydro-pyran ring adopts a half-chair conformation. The mean plane of the four essentia...

The title compound, C(23)H(31)NO, 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. The dihedral angle between the latter ring and its substituent is 83.6 (7)°.

Cr(III) complexes of tridentate SNS ligands have been prepared and evaluated as catalysts for ethylene trimerization, with several giving very high activity and excellent selectivity toward 1-hexene when activated with methylaluminoxane. The new complexes illustrate the potential of sulfur-based ligands on early transition metals for catalysis.

The title structure, C(22)H(22)BrNOS(2), is a triclinic modification. Whereas the other reported modification crystallizes with just one mol-ecule in the asymmetric unit, the present modification has Z' = 2. The six-membered cyclo-hexene ring adopts an envelope conformation, with the C atom bearing the two methyl groups representing the flap. This atom deviates by 0.674 (4) Å from the plane pas...

In the crystal structure of the title compound, C(21)H(18)F(2)O(3), the cyclo-hexene ring has a slightly distorted sofa conformation; the two benzene rings are inclined by 76.27 (8)° and their planes make dihedral angles of 16.65 (10) and 67.53 (7)° with the approximately planar part of the cyclo-hexenone ring [maximum deviation 0.044 (2) Å, while the sixth atom is displaced by 0.648 (3) Å from...

In the title compound, C(17)H(20)N(2)O(4)·H(2)O, the cyclo-hexene ring adopts a half-chair conformation while the indazole ring is essentially planar [maximum deviation = 0.0192 (12) Å]. In the crystal, pairs of inter-molecular O-H⋯N hydrogen bonds link the mol-ecules into dimers lying about inversion centers and intra-molecular O-H⋯O hydrogen bonds result in six-membered rings. The dimers are ...